My cat (7 yr old female) has recently been getting in and out of the litter box constantly. Because of past urinary issues (a bladder stone and a uti) I immediately took her to the vet. The vet did an xray and found nothing wrong. She gave her an antibiotic and sent us home with some painkillers. She seemed fine for a few days but now she's doing it again. There are clumps in the litter box so she is successfully going but she's using it every half hour. And now I just caught her peeing outside the litter box, which she's never done before. For context, nothing has changed in the environment. I've been keeping the litter box clean. And otherwise, she's acting normally. Still has a ton of energy and wants to play constantly. She's also eating (canned prescription food) and drinking normally. Before I dish out another couple hundred to the vet, does anyone have any ideas of what's going on with her?