pregnant or weird body?!?

I stopped taking my birth control about a week ago, well my boyfriend and I have been having pretty active sex, I was out with my best friend today and she pointed out after I peed that I was slight bleeding on the toilet paper, well I had already thrown it in the toilet, so next time I went to the bathroom I looked after wiping and there was very light pinkish blood, my period isn't for another 12 days.

what could be going on?