Do you think that I'm Pregnant?

My boyfriend and I had sex right after my period. We used a condom and he did not ejaculate. There may or may not have been Precum. The condom did not break and there were no holes in it because we filled it up with water after and it did not appear to leak. I think I ovulated but I am not sure. Around the time I was supposed to ovulate I noticed an increase in libido and slightly more "slimey" mucus. I am a day late according to a 28 day cycle but i am not sure that my cycle is usually 28 days. I tend to be a big worry wort and would like to know if you think i'm pregnant? I took plan b about 2 and a half months ago so is it possible that that will still mess with my cycle? How often do unbroken condoms get people pregnant? Should I be concerned?