negative tests, no period, what’s going on

Hi ladies! So I took a test april 14th and it was negative and then waited a week and a half and took another one and it was negative. The last time I had sex was around the early 20s of march. I had a really weird period? Around late april, it was insanely light, almost like spotting, but my test came up negative around that time. I have no pregnancy symptoms, but I don’t have premenstrual symptoms either. I’ve been having a little blood in my discharge, and today I had some pink discharge, but I am 95% sure I am not pregnant. Could it be hormonal imbalance? Should I be worried? Is it dried blood or something? I would like some feedback from some people. I’m almost 21, and I’ve always had regular periods until I had sex with my ex boyfriend. We had unprotected sex a few times, I tested negative for all STDs and had a negative pregnancy test a month after the last time we had sex.