Not too many, I am going through it now too.

All I do is try to control my breathing with deep breaths and I tell myself that it will pass, since it always does. I get myself so panicked with it then I think I am having a heart attack then I think I have died and the list goes on and on. It's a horrible feeling and there's not much to control it but you have to calm yourself down and just tell yourself it will pass like it always does.