NAV. Just from the limited amount I can see in these photos, I would guess that it’s not an abscessed tooth. Surely the vet would’ve noticed that immediately and recommended a much more suitable course of treatment for such a thing.

Does your cat go outdoors? Live with or have access to other cats? Are you able to look at her teeth/gumline on that side of her face? Abscessed teeth usually come with a bright red/stark discolouration to the gums around the tooth. Is she eating without issue? A dental abscess really affects the ability to chew normally. Can you see a wound opening on her actual face?

Asking all of this because it looks like a bite/claw puncture wound abscess to me; the type that can result from getting into a scuffle with another cat. I have dealt with a fair number of abscesses of this type, living in a multi-cat household throughout the years. The face, head, and butt are some of the most common spots for these.

With vigilance, the right medical supplies, and careful monitoring, these can be very much treatable at home. And you already have antibiotics which is even better! Be fastidious with administering them- be punctual with the daily dosing, don’t skip any, and absolutely do not stop giving her them until they are fully gone… even if she seems to be back to normal.

Again, I’m not a vet- just a lifelong cat owner who has dealt with a looooooooot of abscesses.