Hun any time a dog who is older in years starts drinking more and urinating inappropriately its time for a trip to the vet. If you can, try to get a sample in a clean container to take with you to test. Our 10 year old dog has had cystitis 3 times in the past year, the last time I caught it was when she wee'd on our bed! Everytime she's had issues and twice it had grown to her kidneys which affected her drinking as well. Its worth a trip. There are a few things that would cause drinking and weeing more (in vet talk PU/PD) so its worth checking it out.