Hi, Im On Yasminelle 1,5 Year Now And My Last

Hi, Im on yasminelle 1,5 year now and my last period was a little smaller, than other times. Then, at day 4 of new box, I take the pill 10-11 hours late and I also had a few spots earlier that day. Four days after that i had unprotected sex and i realised that I was bleeding. So Im afraid. Is there a change of pregnancy??