bleeding

[https://users.livejournal.com/--7am/]

I recently began having sex about three weeks ago. I don't know if that has anything to do with my problem, but I'll state it just in case. Anyway. I started my period on Monday the 15th. It was a completely normal period, and it stopped the following Saturday. I had sex again on Sunday, and I bled during and after the sex. Just a little bit, and it didn't seem like menstrual blood, so I assumed it was from something during the sex. Ever since then I've been bleeding as if I still have my period. Not heavy and not constant. But still bleeding enough that I need to wear at least a panty liner. Tomorrow I will have been bleeding for two weeks, whether from a long period or something else.

Any advice as to what this could be from? Or if anyone has experience with an exceptionally long period?