I hope that you did not reply back, because you are tending to your cat or you are on the way to the ER vet center.
If this yellow tabby is not spayed, she could have developed a serious uterine infection called pyometra, which must be treated immediately. Typically, the treatment is spay surgery.
If you have an unneutered male in the house that has impregnated your other female, he should be neutered, asap.
If your cat is spayed, she may have a urinary or bladder infection, which can cause bleeding, or she could have another problem, internally, that is causing the bleeding. It's very important to find out the cause of the bleeding and stop it, right away.
Could she have gotten into any rat poison? Many of these include a substance that causes uncontrolled bleeding, as it removes the clotting factor from the blood.
If you haven't yet, please bring her to the nearest ER vet (unless your vet has emergency hours) to be evaluated and treated.
I hope all will be well with your furry girl and please let me know how she's doing and what the vet tells you. Thanks!
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