Sounds like it could be her kidneys. Your best bet is a trip to the vet immediately. Ask some advice about general diet too, and maybe the roasted chicken maybe too much for her. Raw chicken would probably be better, and a few raw chicken bones good too, some fish would for a change could be good for her too. But definitely a trip to your local vet for her. Good luck and if you can let us know how she does.

I would offer the same advice. Take her to the vet and have this checked.

Definitely you want to take her to the vet, butI can offer you my cat's experience. He was 16 years old and had kidney trouble for several years; one sign of this is frequent drinking and frequent urination. The increased frequency in your cat could be developing kidney trouble or simply advanced age. The back legs sounds like there may be some arthritis forming (again, I'm not a vet). Our vet gave us an inexpensive prescription in powder form and it proved very helpful. 14 is pretty advanced for a cat and you may find yours beginning to decline or become ill. Changes in habits is pretty common; don't be suprised his she picks a more convenient place than her litterbox to use. One note: If things progress to the point your cat seems to have more trouble and pain than pleasure in her life, I cannot recommend highly enough the option to have a vet come to your home to put him to rest. It's a peaceful experience that minimizes your cat's stress and pain. We were averse to any actions that didn't feel like the natural progression of life, but in retrospect I feel we gave our little guy the rest he'd been seeking. Good luck. And never, ever feed your cat or dog bones; they can splinter and puncture the intestines, leading to serious complications and sometimes death.