Just wanted to give a final update: All better! No swelling at all.
That being said, I'm not sure if it was the antibiotics or not. The swelling hadn't reduced by yesterday PM even after nearly 3 days on antibiotics. However, we had a very gusty storm last night, knocking the power out and causing me to temporarily move them from their brooder in the shop (which has pine shavings for bedding) to a large dog crate in my upstairs bathroom where I could fill the large metal tub with hot water and use it as a radiant heater. In the new environment, they were on a towel instead of shavings- maybe the lack of dust helped? I wonder if a pine bit got stuck in her sinuses, and the dust was exacerbating it. Unsure. Happy she's better, though!
Edited by ChickenHermit - 3/10/16 at 10:45am