Hi Shay,
In older cats, sometimes these symptoms just appear and then the reason has to be tracked down by your vet through testing and a process of elimination, if tests aren't conclusive.
Is she walking normally and just can't jump/run, or are her hind legs weak also?
If your cat has suddenly started drinking more, urinating more, eating a little less, acting pretty tired most of the time (I know senior cats sleep 99% of the time--I HAVE one, too! : )), these symptoms might be related to diabetes and diabetic neuropathy. This is a condition brought on by uncontrolled diabetes and affects the nerve impulses to the hind legs and surrounding areas.
Another possibility is an injury to the spine which is adversely affecting her hind legs and control of bowels; a neurological problem.
There is a condition called a 'saddle thrombosis', in which blood clots can be developed and lodged in each leg causing paralysis and/or hind leg weakness. This condition is usually associated with feline hypertrophic cardiomyopathy, a serious heart condition. It's treatable if caught early.
I know this sounds scary, and I don't mean to scare you; I'm just supplying you with some possibilities for your cat's recent symptoms.
When was your cat last checked by the vet? I would strongly suggest that you bring her in for an evaluation and diagnosis, then the proper treatment will be prescribed. Don't wait on this, get her in to see the vet as soon as possible.
Please keep me updated on how she's doing and what the vet tells you. Thanks!
Cher
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