Trust ME you REALLY feel all these symptoms!!! Sometimes it can be just one of them....Other times all of the symptoms at once!!! I have panic attacks and they SUCK!!! Sometimes I able to fight them off but trust me there is times I have to reach for my Meds!!!! Hopefully you NEVER experience one of these attacks BUT if you do I am POSITIVE that you wouldn't be questioning if the symptoms are imaginary ones....
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I'll try to sum everything up for you since I have an anxiety disorder.

Image yourself being in the worst possible situation for you. I can be in a room full of needles, being faced to face with a predator...anything that would an intense fear to you. Now, take those feeling of the situation, and place yourself in doing everyday tasks...like driving or being in a crowded room. You're freaking out, but don't why...and there really isn't a reason why.

Believe me, the symptoms are completely REAL...and a full blown panic attack is just about the most horrible feeling in the world. All that it's basically caused by is the "fight or flight" response being activated...meaning you have a huge increase in adrenaline rapidly instead of gradually. Blood flow is reduced from most parts of the body, and more is pumped into the biceps and legs, which causes the dizziness (from lack of blood and oxygen in the brain, though it's extremely uncommon to actually pass out from a panic attack), hot flashes, and paleness of the face, hands and feet.

All of the symptoms are pretty close to those of a heart attack.

~Take Care~
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Yes, panic attacks are very real and and extremely frightening. Doctors are not sure exactly why they occur when someone feels anxious but when they do, they hit like a truck, and induce not only the laundry list of horribly uncomfortable physical symptoms of being in a situation of extreme primal fear, but also an uncontrollable psychological feeling of absolute terror that you can't seem to make sense of and can't make go away. You really feel as if you are completely losing your mind and are just going to pass out and die even as your logic tries to convince you that can't happen and there is nothing to fear. And the only thing you can do is just try to breathe and wait for it to pass, which usually takes about 10-15 minutes or so and seems like an eternity at the time. It is one of the most terrifying things I personally have ever experienced.
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Trust me you don't want to ever experience a bad one, like CJ above said they can cause pain that makes you think 'heart attack'. Symptoms can vary from slight to extream.
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When I had panic attacks a while ago, I usually had these symptoms:

-Very high heart rate, felt like my chest was going to explode.
-Feeling of breathlessness. Made me have a difficult time respirating, and so I would struggle for air.
-Numbness. I would usually feel numb in my wrists, neck, traps, and feet. After the attack, I would often feel very exhausted and fatigued in these areas.
-Increased body temperature. I'd usually begin sweating.
-Shakiness and dizziness- self-explanitory.

These attacks can really be awful....its like you uncontrollably begin suffering these things, and feel like you are gonna just pass out at any moment, but cant. Then, when its over with, its like a reaction to just start bawling and panicking.
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I have suffered from panic attacks for over 8 years now. They can be provoked by circumstances/situations or just come on without warning or reason. I have not had hot flushes. I become very frantic...pounding heart, shaking hands, irrational thinking, sweaty palms, spontaneous hiccups, crying and/or agitation,rapid breathing ( which can lead to light headedness if I don't get my breathing stablized). They really happen. There is nothing imagined about it. It is frightening and difficult to take control of.
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They feel them for real. Panic attacks have all the same physical effects as if you were really in danger. The fight or flight response kicks in and causes the body to respond in real ways (elevated heart rate, increased respiration, etc).

We respond the same to fear no matter what the cause. If you jumped when something pops on the screen during a scary movie, isn't it the same response as if someone really jumped out at you?
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yes it go on i know
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What is generalized anxiety disorder (GAD)?
Everyone feels anxious from time to time, like when they have to meet a deadline or deliver a presentation. But for people with GAD, a constant and exaggerated sense of worry interferes with their daily life. People with GAD tend to expect the worst when dealing with issues related to money, health, family, or work, even when there is no sign of trouble.

About 5% of people in the U.S. will have GAD at some point during their lifetime. Each year, about 3% of the U.S. adult population has GAD (approximately 6.5 million Americans). Nearly twice as many women as men are affected.

What are the symptoms of GAD?
People with GAD may experience a few symptoms or may feel overwhelmed by many symptoms. The key signs of GAD are anxiety and worry that are difficult to control and have lasted for at least 6 months. In addition to excessive anxiety and worry, people with GAD have at least 3 of the following symptoms:

Restlessness or feeling on edge
Fatigue
Difficulty concentrating or mind going blank
Irritability
Muscle tension
Difficulty sleeping
Some additional signs associated with GAD include:

Symptoms associated with muscle tension, such as trembling, twitching, feeling shaky, and muscle aches and soreness
Physical symptoms such as clammy hands, dry mouth, sweating, nausea or diarrhea, an increased need to urinate, trouble swallowing, and an exaggerated response to being surprised
People with GAD often have symptoms of depression as well. In fact, 2 national studies found that between 58% and 70% of people who suffered from GAD in their lifetime have also suffered from depression at some point.

What are the causes of GAD?
Some research suggests that GAD may run in families. It may also grow worse when a person is under stress. Although the exact causes of GAD are unknown, it may be due to a chemical imbalance in the brain. Serotonin and norepinephrine are 2 chemicals used by some nerve cells to communicate. These chemicals, called neurotransmitters, are thought to be linked to GAD. Therefore, medications that affect these neurotransmitters may play a role in treating GAD.

Take action if you believe you suffer from GAD
If you're experiencing symptoms on a regular basis, or have been diagnosed with GAD, treatments are available that can help you get back to your life again. Talk with your doctor about your treatment options. The right treatment could help you reach the goal of treatment — virtual elimination of symptoms and keeping them from coming back.
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effexorxr.com

I assure you, they feel them. These symptoms are very real and often mimic the symptoms of a heart attack, which naturally adds to the panic.
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Life, education, reading, and several panic attacks.

They're faking it for attention.
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