Hello and thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 30 years of experience and would be happy work with you.
If she just recently was examined by your veterinarian and nothing more than a UTI was noted, I would be less concerned that this is due to a physical ailment, but I would make sure to have her urine rechecked to see if the UTI has resolved. If it is not a physical problem, it may be that she is starting to show signs of cognitive dysfunction that comes along with aging. This is similar to dementia in humans, but in the very early stages may present as nothing more that increased vocalization for unknown reasons. Over time, other symptoms can occur and can include wandering aimlessly, staring off in space, seeming unaware of surroundings, night howling or having changes in sleep wake cycles, seeming slightly disoriented at time and urinating and defecating outside the litter box intermittently.
I would talk to your vet about this and keep track of any other changes in behavior that may come up in the future.
I hope this is helpful. Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please reply so I can clarify for you.
My posted replies are for general education only and not meant as a diagnosis. Only after a thorough veterinary examination can a diagnosis for your pet be made and specific treatments be advised or medications be prescribed.