Black blood and some small clots for the past three days some small bit of blood in urine never had black blood before period always end?

Needs assessment: 2 things are needed fairly promptly here: 1) a pregnancy test and if positive urgent medical attention and 2) a urinalysis to check no infection. There are a variety of other possibilities including pelvic infection, other urinary tract problem that require examination and tests but rapidly excluding a pregnancy related problem or kidney infection is quite important. All the best.

I am quite confused: by your description. Is this your period? Is there black blood coming from your vagina with small amounts of additional blodd in urine? If you are menstruating right now - black blood is old blood being cleaned from the uterus. If there is blood in your urine - is it coming from the vagina & mixing in with urine. If you have bloody urine you need medical assessment.