Hello Doctor. I Had Sex For The First Time Using

Hello Doctor. I Had Sex for the first time using protection this 26th of April.And My due date for period was of 8th May. I am Not having regurlar flow of Period with Clotting like I used To. Instead I am Having Red bleeding which was for a day. So Is it spotting or periods ? Is there a possibility of me being Pregnant? If Yes What should I do ?