Bleeding between periods but a few days after sex

Patient: I recently lost my virginity and the first couple of times I bled a little but it went away quickly. However, this time around I didn’t bleed until two days after. It is bright red and there is Enough blood to signal the beginning of a period but I am not due to get it for another two weeks or so. What can cause this? I admit the sex was a little rough. Could this be an early period or implantation bleeding? We used a condom every time. I have mild lower abdominal discomfort. Any advice or information would be greatly appreciated. Thanks