pregnant?!?!?

i was wondering what was the possibility of me being pregnant, I'm at weeks 8 week pp, i got on the pill on the 12th and had unprotected sex on the 17th even tho i know i wasn't supposed to, now im spotting since last night, could this be implantation bleeding or spotting because of i recently got on the pill? please mommies i need some advice I'm freaking out