This has been going on for about 1 week. It started very suddenly. Kitty went from in/out all.day.and.night, waking us multiple times--to now. She has found a spot on the grass near our driveway. She comes in only to eat and immediately goes back to the exact same spot. She has worn the grass away.
She is responsive to petting and will meow in greeting when I come home. She does not seem weak or in pain. She is eating fine and not excessively. I don't notice excessive thirst. Is this lethargy? Someone asked if she's a hunter and she is, but she doesn't seem intensely focused on potential prey out there. She refuses to stay in the house. This seems to have happened literally overnight, but she does not seem distressed. She is at least 16 years old and has never been sick a day in her life. Any ideas? Thanks.
Thanks for the replies. Yes, we will be taking her to the vet. It's become clearer that this is not just a "phase." At first, we thought she had just seen a bird or mouse, as she's always been a big hunter. Now I'm sure something's wrong. I sat down beside her in her "spot" this morning and she climbed into my lap. In many ways, she's still very much herself. But something is obviously not right. I can't tell about peeing and pooping, because she's not inside long enough. Of course, we will likely face that question about how much testing and treatment we should pursue, given her age. But she's been so healthy, I really think she'd stand a good chance of recovering if we could find out what's wrong.