Yep. Bella's injured. After a full night of carrying her everywhere, Kris called the vet this morning. We took her in for an appointment, where Dr. McClenahan checked Bella over.
Two relatively howl-free X-rays later, we had confirmation of a torn cruciate ligament.
We're supposed to keep Bella off her leg as much as possible, but let her walk if she wants to (she can't injure it much worse), give her painkillers daily, make sure there's no rough housing with Annie, run Annie a lot to tire her out, and see how Bella is in a week. If she's having problems in a week, consider surgery.
Surgery. Great. After the $300 bill for the diagnosis, we'll have another $3000 bill for the surgery. Whoo.
Now, why didn't we get a cat?