My boyfriend and I got caught up in the heat of the moment on Jan. 16. We had unprotected sex and used the Pull Out method. According to my ovulation calculator I'm fertile between Jan. 14-17. I ended up taking a Plan b pill today, about 18 hours after the sex occured. I'm just a little paranoid as I heard about pre-ejaculate and plan B might not being effective during ovulation.
What are the chances of pregnancy occuring?