From uti or implantation?

So I just recently found out I had a uti (but I've taken medicine for it, it is almost gone) and before I found out I had a uti, I had sex 9/3,9/4,9/5 (I just seen my boyfriend after a long dry spell, no judging 😂😭) but today when I used the bathroom I had little mixtures of clots and they were either brown or light red. I know implantation is rare but I believe I ovulated earlier than I should've and my period isn't due till 9/24. What could it be?