my period is late for 7 days now i have took 8 pregnancy tests in total they all came back negative i've been nauseos and really tired i have an appointmen on wednesday to do a blood test, in very regular, im on the pill and the day i was supposed to get my period i just spotted brown discharge and then nothing till now and also in having really bad cramps since last week .

and also i want to point out that i think i might have a uti could that be the reason why my period is this late?