Brown stuff in my underwear

Emily • It’s not always the best idea to follow the masses, because sometimes the “M” is silent.

I just recently finished up my period, and I'm currently ovulating. But lately, I've been finding this weird brown stuff in my underwear. It looks sorta like the underwear stains you get from not wiping your butt after pooping. But I know it's not poop because it's on the front of my underwear (where my vagina would be.) Can somebody explain what this is, because I seriously have no idea.