Okay, so my last period was around December 20th, 2015. Then I had sex on December 29th. According to this one app I use to track my periods, it was the time I'm supposedly ovulating and the very peak day so most fertile time to get pregnant. He cum on my tummy but I was scared few drops went inside so after an hour, I got plan b. Then on the January 7th I got some bleedin for 4 days. It was not my period tho. I was thinking oh it's my plan b side effect, like dark blood not the bright red. So all January I got no period. It's February now and I thought maybe I should go by the plan b bleeding cuz sometimes it can start new cycle. Still I didn't get the period on February 7. Now I'm really nervous and I don't know if I'm pregnant or when I should be expecting period. Thanks