We are near Holmfirth West Yorkshire and only see Robert Whyte at Donaldsons Vets in Thongsbridge. It's a bit of a drive. I'd ask if they will scan her to see what is going on inside. It sounds as if it would be worth finding out as the antibiotics are not working to reduce the swelling.
There is a vet finder here which you could check through for a nearer vet baring in mind some of the recommendtions are quite old
Good vets finder