Yeah, the feeling of passing out in any moment made me to go to ER many times. But after several frustrating trips I have given up. I have told to myself that as long as I can walk there myself, I don't belong there. I agree with your thinking though.. even knowing that I won't get any help from ER, I have went there because I have been thinking that if I pass out alone at home, there's no one going to help me.
I am rather sure that my feelings are out of proportion because nothing serious has ever happened. The first moments have resolved themselves. But this feeling I am having right now is really crap. It's something that you just want to go away. But it's inside you so where do you run. Just live it though.. and hope that one day it will be better or the meds kick in.
But have to say that by reading similar stories from others, makes me feel more confident that this is anxiety related and can be treated and most importantly that I am not alone.