What’s it like? It’s not unlike having a bit of food stuck in your throat. You can’t breathe. Your head is spinning. Your heart is pounding in your chest and soon a deep sense of dread spreads through your limbs. Your head screams at you to do something, anything. In my case, it wants me to leave whatever situation I am in. It doesn’t matter where I am at the time. Usually, I’m trapped. You can’t abandon a group of friends without a word, or run out of the supermarket. So, you try to act as if everything is normal while you feel sick. You’re in a state of panic and, in the worst cases, you have the deep suspicion you are about to die.

http://www.theguardian.com/commentisfree/2014/may/18/living-with-anxiety-coping-mechanisms