Paranoid

I had sex with a guy a couple days ago and I'm on birth control (near the end of my 21 active pills, was only late taking them once this month) and we didn't use a condom.  I know, not safe sex, I'll definitely use a condom every time I have sex from now on.  I didn't let him come inside of me, but he came on his own stomach without really warning me that it was about to happen and now I've been paranoid that I might be pregnant. Note: I still have 2 more active pills and haven't started the sugar pills yet.  Can someone please calm me down, my friends keep saying I'm fine.