Two weeks after my last period started, I made a dumb decision to have unprotected sex with my boyfriend (really bad timing and just decision overall). He used the pull out method, which I know isn't really safe at all, and I freaked out so within 72 hours I took the One Step Plan B pill. Two weeks after that incident, which would also be when I'm expecting my period, I had awful cramps (which never happens to me on my periods) and only a tiny light spot of tannish blood. What are the chances that I am pregnant, and when should I take a pregnancy test?