Yes, I regularly wake in the middle of the night, from a sound sleep, in total panic mode. It's been a problem for me for years. I'm 35 now and I can recall it happening regularly from when I was in sixth grade and maybe even before.
I'm currently on Prozac, and while it does still happen to me, it's far less intense than it used to be. Now, I will wake, acknowledge that I'm in panic mode, and be able to settle myself back down within an hour. Before, I would be awake for hours, sometimes I'd never go back to sleep.
It su-huh-huh-ucks. Unfortunately, I have no helpful hints for you, but I wanted to let you know that you're not the only one. If it helps you, you can think of me in the middle of the night when you're up. Sometimes part of my anxiety has to do with feeling alone and isolated.
Hang in there, maybe your ob/gyn will have something helpful for you.