I have been on Birth control for over a year now and I have not missed a pill in several months. About a week ago my boyfriend and I had unprotected sex and he ejaculated in me. I still took the plan B pill  just in case. Everything wa fine until about a day ago, when I noticed I was bleeding. It was like spotting. Every time  I went to the bathroom I would notice a hint of red or a little bit of blood. Is this normal or should I be concerned?