I've made an emergency appointment at the vet's for an hour from now.
I was noticing yesterday that she looked rather jowly, with her dewlaps hanging down. I just thought she was being matronly (she'll be six years old this month). But as I was petting her yesterday, I felt what I thought was a loose fold of skin hanging down from her jaw, which may have been an abscess or something. If so, that probably burst, causing her some pain, fear, and maybe a fever.
It ain't gonna be easy to get at her problem, since she doesn't like strangers much, and vets much, much less. They'll either have to muzzle her or sedate her, I'm thinking. Either way, my guess is the rest of this day is going to center largely around dog care.
EDIT: Sassy was obviously agitated, but behaved pretty well at the vet's. They're keeping her. Gotta sedate her to shave her ruff at the affected area. Sedation means pre-op bloodwork, yada yada. We're talking around two hundred simoleons.
My guess is, she's got an abscess there that broke open. It began bleeding again -- profusely -- in the exam room upon being handled. It'll have to be drained and she'll have antibiotics to take for a while. Anyway, we'll see what the vet has to say in a bit.
Further edit: For her many admirers, here is her gallery of photos. http://pics.livejournal.com/aefenglommung/gallery/0000ft6t