That's not urine. Snakes don't urinate in the same way people or other mammals do. What you are talking about is musk. That's a defensive behavior. She's expelling the contents of a musk gland hoping you'll leave her alone because of the smell (she sees you as a potential predator). Notice the white, gritty, chalky stuff in her cage when she poops? That's her equivalent of urine. It is in the form of uric acid crystals.
As for the blood that is present, it could indeed be from parasites or from some bacterial infection. What you need to do is get a stool sample and take it to a vet for analysis. It needs to be fresh (no more than 4 or 5 hours old at most). You can collect a fresh sample and put it in a plastic ziplock bag and keep it in the refirigerator for up to a day.
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We do not inherit the Earth from our ancestors; we borrow it from our children. Ralph Waldo Emerson