Please be helpful, not rude. SOS

I just got home from my boyfriends house and realized that I've missed my pill for a few days. Irresponsible I know. It looks just like one of my others I take is for some reason it didn't dawn on me that I wasn't taking it. But in those three days we had sex one time which was last night and he finished inside me. But when I woke up this morning I had started my period. Does that mean there isn't a chance of me getting pregnant this time? Please help. I've never had this happen