What Causes Blood Clot During Urination While Having PCOS?

I am having throx 100 for thyroid from 3 years and metformin for PCOD thrice daily since 2 weeks and my last menses was 3 months back and today i had blood clot during urination and i have checked with urine pregnancy kit and the result was negative. i want to know why i had a clot and i want to clarify whether i had concieved