Blueviolet, I don't want to go too OT but in answer to your concerns about keeping cats indoors, they aren't desperate to get out if they are kept in from the time they're kittens. 
I can see how adopting an older cat who's used to being out might be a problem, but I had many cats growing up. The ones who were always raised indoors are very happy. In fact, I remember once when we left the door open and one came creeping outside, looked at the big wide world, and tore back in the house! It was too scary out there! :LOL Seriously, cats that are raised in the house are so much better off. In the last month, there have been two cats hit by cars down the street; my neighbor's cat came home with fight wounds (which abcessed and cost $150 to treat)... and like I said, it's only a matter of time before one of their cats will be killed by my dogs. 
Cats don't care about fences, and leash laws will have no bearing when it happens in my fenced yard. It will be my neighbors' fault, because I begged them the day they brought those kittens home not to let them roam.
I can see how adopting an older cat who's used to being out might be a problem, but I had many cats growing up. The ones who were always raised indoors are very happy. In fact, I remember once when we left the door open and one came creeping outside, looked at the big wide world, and tore back in the house! It was too scary out there! :LOL Seriously, cats that are raised in the house are so much better off. In the last month, there have been two cats hit by cars down the street; my neighbor's cat came home with fight wounds (which abcessed and cost $150 to treat)... and like I said, it's only a matter of time before one of their cats will be killed by my dogs. Cats don't care about fences, and leash laws will have no bearing when it happens in my fenced yard. It will be my neighbors' fault, because I begged them the day they brought those kittens home not to let them roam.
It would help if people would act responsibly with their dogs (though since cats roam everywhere, that's not always enough). I do think all cats should be indoor-only, because that's the only way to protect them from fighting, disease, cars, raccoons, poisoning, and especially dogs. An indoor cat has about double the lifespan of an outdoor cat. I knew a couple of 20-year-old cats when I worked as a vet tech!
But if you're not having any symptoms of illness... and your bleeding is okay... I'd say to just assume that your body is taking care of it. Just don't put anything up there, eh?
:LOL but my cat lived to be 17, and my in-law's cat lived to be 21. My mom went through a string of three cats who simply disappeared (she thinks they were killed by wild animals) when only a few years old, and now has had the same cat for several years. All outdoor/indoor cats. I'm kind of inclined to think that cats, like people, have varying degrees of intelligence and luck and, like people, can meet an untimely demise or live a long life depending on those factors. I do feel it's better to live well (as I define it of course) for a short time than live what looks to me like an unnatural, deprived state for a long time. But everybody draws their risk/benefit lines in different places, and that's okay. Kind of like birth, huh?
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