Plan B/Choppy Birth Control Use?

Allie
I had unprotected sex last Saturday and I had been on the pill for almost a month after starting mid cycle. During this time and a few days prior, I had been experience some heavy bleeding and cramping due to the fact that my regular period was due at the time. I would classify my pill use as "typical" and not "perfect." A couple of days I would take 2 in one day (due to traveling reasons) and then not take one the next day. I would also take my pills within a 3-4 hour time frame instead of taking them at the exact same time. A little less than 48 hours of the incident, I took Plan B because I was worried. It's now been a week since I've taken the Plan B and I've experienced no bleeding. I know I hadn't been perfect with taking my pills (still learning and getting adjusted) and did put myself at risk, but what do my chances of pregnancy look like?