Any advice for this anxiety?

I don't understand... I've had 5 pregnancy tests, a vaginal ultrasound,I'm on birth control and had two periods. The most recent one was bright red and heavy for about four days till it tapered off for the last two. I filled several pads.

But why am I still getting nervous about pregnancy? It's been two months of this constant worry. I have GAD (Anxiety disorder) so that makes unrealistic things real to me.

It's gotten to the point where I'm too afraid to have sex at all. Does anybody have advice for this? Thank you..