I had unprotected sex with my boyfriend (from Sept 2 to Sept 6) before I started my period on Sept 6. And through Sept 10. I was on the pill but it was my first month. It was a short period. Mine usually last for 6 or 7 days. But it stopped on the 11. I spotted (it was very very light pink) on the 15 and 16th. Is there any possible way that I could be pregnant? Or anybody with similar stories? Thanks