I Was Wondering If Theres A Possibility That I Can

I was wondering if theres a possibility that I can be pregnant. I am 3 days late and I'm usually always right on time on my periods. I've always been regular. Last month I had unprotected sex the day before I started my last period and that period was completely normal. It lasted about 5 1/2 days and I was heavy just like usual. Could I be pregnant from the sex I had the day before my last period? He pulled out but of course theres always that chance but im doubting im pregnant since I DID have my period after that last month.