I am late on my period by a couple days. This could be from stress, however, the question of pregnancy comes up, due to events last month. Last month, the condom broke, so my boyfriend bought me the morning after pill. A day later, I experienced a flow of blood which lasted rough 4 to 5 days. I took a pregnancy test two weeks later, and it read negative. So I haven't worried about it since. However, I have missed my period, and I'm wonder if it's stress, the plan b pill messing with my system, or the pill didn't work. This was my first time using plan b. Help is much appreciated!