Light bleeding/spotting after sex?

Before I ask, I have PCOS and am 4 days late. I’ve taken pregnancy tests and it’s a BFN. I’m not sure what it could be and I’ve looked up on it too but I’m not sure yet if it’s any of the vaginal diseases (sorry I don’t know how to refer it to). I don’t have medical at the moment but I’ve noticed since 3 days before AF shows I had sex with my S/O and I bled a little bit when wiping once for 2-3 days and then stopped. We ended up having intercourse today and I’m bleeding a bit again when wiping only. I noticed that while having intercourse I was in a bit of pain as well. Do any of you know what it could possibly be? 🥺 TIA!