Is this normal I’m 3 months postpartum by c section ?

So I thought I had a UTI about a month 1/2 ago and my doctor told me no. But I already had my period from July 17th-21st & now my back hurts bad, as well as stomach cramps. I’m tired like crazy, head hurts, and when I pee it looks like stringy things are in it as well as like little circle drops of blood. And when I wipe there was this, it looks almost black I don’t think it’s normal. Any ideas ?