Well the vet finally called and I could actually talk to her. Mitzi has a cyst on her right kidney and a stone in her left kidney. Neither are causing any blockage right now. No surgery to remove the cyst - just a change in Mitzi's diet and regular monitoring of her kidney function. She seems to be ok for now, at least we know what's going on and what to watch for.

I also scheduled a teeth cleaning for her with another vet who will do it in a safer environment, without anesthesia. It won't be until the end of March, but I think I'll be more able to handle it both physically and financially by then - it's also MUCH cheaper than what this vet charges.