She needs an antibiotic. Sulfa is best. But it will take more than a week to get it by mail. I ordered some here https://www.jedds.com/shop/trimethoprinsulfa-100-g-medpet/ to keep on hand in case I ever need it I won't be watching chickens die while I wait on the USPS. They always used to call it "snail mail", but now we need to come up with another name for it, snails being faster than the mail these days..
If you live in a big city, you might be able to find pigeon sulfa which would work.
If you live in a big city, you might be able to find pigeon sulfa which would work.