I'm the same way to the point where after I had DD and DS I wouldn't use things that I didn't use when I got pregnant with them, because I would think, "What if that messes up my chances of conceiving?" Crazy, I know, but it's me. My DD has a really bad habit of kneeing me in the abdomen when she's laying with me on the couch and I start to spaz out in my head, and occasionally on her.

I worry about sitting at the computer too long and cutting off blood flow to my uterus. (I don't even know that that's a rational thought, but it's my thought process at times just the same). I think mine has to do with my anxiety disorder too. Try to breathe.