Late period?

So I had sex 4/15 which was 3 days after my period ended. We didn’t not use protection but he pulled out and i’m pretty sure nothing got in me. I usually have 4 sugar pills in my old brand of bc. I just switched birth control brands & dosages. I am not taking Estraylla. Last month was my first month taking it and I had my period for 6 days and it started when i took my first sugar pill. This month I just took my second sugar pill and no period. I have tender breasts and ive been spotting for a week like I normally do before my period. Could I be pregnant?