I finished my period on the 13th of this month . Two days later my boyfriend and I had sex. The condom broke and he was nervous and got me a plan b pill. I took it immediately. On the  20th ( yesterday) I got my period again. And it's only 6 days later. Now I'm thinking it's the pill causing this but my boyfriend did some research and there's a website that says it. Can be early signs of pregnancy if I'm spotting, I have fatigue, cramps, headaches and nausea. To me it makes no sense because if I'm on my period, I'm shedding my eggs, so how could I be pregnant. It'd just weird how it's not even a full week and I have my period again, it has to be the pill right?