Why Is My Cat Peeing Blood?

I think my cat is pregnant and she is peeing blood the past week I have noticed that she has gained weight and has became protective of her stomach she is keeping to herself and I don't know what to do
PLEASE HELP!

Being in heat does not make cats urinate more frequently and does not result in blood in the urine.  Bloody urine can be a sign of a urinary tract infection, kidney infection, bladder stones, or if this is a male cat this could be feline lower urinary tract disease.  Feline lower urinary tract disease causes a sterile cystitis--this is an inflammation of the bladder wall without an infectious cause.  It is usually due to stress.  Male cat with either infection or sterile cystitis are at a risk for being blocked--this is when the lower urinary tract (urethra) becomes obstructed by a mucous plug or bladder stone and the cat is unable to urinate.  This is a life threatening emergency.  
Your cat needs to be examined by a veterinarian to determine the cause of the bloody urine and start appropriate treatment.  Initially an examination and urinalysis will be performed.

You should observe her minutely. Check it out if it is licking its genital parts as well. Is it urinating in small quantity? Is it urinating more than often? Is there burning sensation of its bladder inflammation? If you observe all these symptoms then it is possibly suffering from feline lower urinary tract infection. Take it to vet soon. If this problem will lead it to urine blockage then there will be a danger of kidney failure. Antibiotics will be given to treat this problem

If your cat is a girl it's probably having her period. And it depends on want frequent means. Does it mean monthly for a couple days?If not,your cat might have kidney failure. I s your cat not eating normally? Is she super skinny? Is she old? If she is any of those things,I suggest you take it to the vet.

This could be serious. Take her to the vet.

Sorry, do you mean you ran her over in your car? If so, surely you've taken her to a vet? Being run over and now peeing blood indicates internal bleeding. She needs medical attention fast.

The one thing you can do for him is get him to a vet,he most likely has a bladder/urine infection,it can easily be treated with a course of antibiotics off the vet,bladder infections symptoms are frequent urinatingwith straining and containing blood,

Its very important to be treated as if delayed can ride up and lead to a kidney infection,so by getting him to a vet now you will prevent further problems and discomfort for him,so make that appointment,one of my cats suffered with bladder infections often but cleared well with antibiotics.