Pink brownish discharge

Hailey

I have a very irregular period, I have two uterus’s also. I had unprotected sex about two ish weeks ago and now this is happening. I was supposed to get my period Sunday, I just took a pregnancy test and it says negative but idk if I tested to early. I’ll post a pic with what it looks like but I have no clue what’s going on tbh, any input helps!! Thanks guys!!