Could I possibly be pregnant??

So me and my SO have been together going on 6 years this year(in November) and we have never used a condom and I have always been on and off with my BC. I haven’t been very on top of it with my BC pills. Anyways- my period ended on the 17th or 18th of this month and then I just got it again yesterday night(27th) after unprotected sex. Also, we had sex on my period and before and right after, but I have never gotten pregnant. I have been questioning if one of us is even fertile. He isn’t exactly the best at pulling out. Lol but anyways... Could I possibly be implanting bleeding? It started off brown and now it like a light fresh red. It’s not heavy but it’s not spotting. Please someone help me try to figure this out?