Brown discharge?

So at the end of May I finally got my period after my miscarriage in the beginning of April then I missed my period in June and July. I took several pregnancy test and they were negative. Last Monday I had brown discharge on my toilet paper when I whipped so I thought I started my period but all week it was just brown discharge. Saturday I had nothing so I just assumed that it was over but Sunday I had blood in my underwear but all day today it has just been brown discharge. Does anyone know what's going on?