Wow, this sounds similar to what I'm experiencing! My kitty is a 13 yr old domestic longhair. Just recently she started that same behavior & I attributed it to her not liking my changing the type of litter I used & went back to the other stuff... that worked for a little while, but she started up again, going in corners of different rooms... but the last time she did it, it scared me because it looked bloody & mucosy... I'd never seen it that way before. The first thing I thought of was I need to get her to the vet, but I've been unemployed for months & have zero dollars for emergency expenses. She was fine yesterday & I'll keep an eye on her, but I sure could use some answers too