am I overreacting?

So I had sex with my boyfriend on Feb. 18th. We used a condom. He peed and then a few hours later he stuck in half of his penis into my vagina without one on. He pumped once or twice then took it out. I am on birth control pills and have been for four months now. I was very worried about pregnancy. My period came on time (according to my pill packet) and lasted 6 days. Yet I am still freaking out about pregnancy. I know it sounds stupid, and I know how pregnancy works. I just can't calm myself. So I guess what I am trying to ask is, do you ladies think I am okay, that I am not pregnant?