Mike,
I know what you are feeling. In August, my anxiety hit again and I did not sleep for 7-10 days. My Dr. prescribed a sleeping pill and that helped. The lack of sleep amplifies my reaction to anxiety. I was on the sleeping pills for 4 weeks and then I got back to my regular sleeping pattern.
As for not going out with friends, you got to go. By not going out with them you are only giving in to the anxiety and keeping the circle of fear going.
Think to yourself, what is the worse that can happen? You have a panic attack - so what!!! They are your friends and they won't look at you like you are weird or something is wrong. Heck, you might find out they have family members or other friends that have a similar condition.
The quicker you return to doing things like going out with friends and socializing, the faster your anxiety will decrease.
From my personal experience, the first couple of times you go out with your friends, you will definitely feel anxious. Likely worrying about whether they notice if your anxious. Eventually, your body will realize that there is nothing to fear in these situations and you will feel alot better.
For me, I had to do many things again and again to reduce my anxiety. Mainly because I began avoiding things (like driving).
If you face your fears (don't avoid anything) you will feel better much quicker.
Good luck.