Brown discharge two days before my period

Hey. My period isn’t due until Saturday. It’s Thursday, and I just wiped and saw brown mixed with my discharge. I’m only on cycle day 25. So it’s a little bit early for my period to start. Plus, when it normally starts, it isn’t brown; it’s either pink or red. Brown means old blood…. So what could it be? I know you guys don’t know, but has this happened to anyone? Any guesses or hypotheses lol?