am I pregnant?? help me!!!

Hi I'm 15 and my boyfriend and I didn't have sex, but we were fooling around and he came in the area between my hoo-ha and my belly button. How likely is it that I'm pregnant?? I know the chances are pretty low but what if some of it got into my vagina and swam up? I was ovulating at the time. I'm also 3 days late on my period any comments would be very appreciated!!