Help period or something else?

I am nine days late on my period and have taken two pregnancy test and both negative but at night on day 8 I started spotting little brown I assumed spotting and today day nine I woke up and no blood or spotting but when I pee blood comes out like it's all red but that's the only time I'm bleeding. 
But prior nights I've been having like terrible heat flashes...
Do yall think its a UTI? Miscarriage? I don't know what to do anymore.