I took Zev to the vets, where she was inspected very thoroughly. Aside from a slightly elevated temperature, there's nothing clearly wrong with her. The vet gave her an injection to lower her temperature, and told me to bring her back in again tomorrow, so she can check her over again and see if things have changed.
After getting home, I gave her some supper, and she inhaled it, so either the injection worked wonders remarkably fast, or whatever the problem was, it's just naturally going away! 🙂
She is also on lock-down, for a day or two!