This is the second time I’ve written this reply – I have to be honest, it looks exactly like my Henry when he had mites BUT his wasn’t red like your bun. And the symptoms are simular…. Henry’s was in the same spot, fur missing, with a sore, and white flakes, but his bare patch was white, not red. And it did irritate him, how I knew to look. I treated it with Revolution for puppies and kittens and applied antiseptic cream to offer some relief from wanting to scratch. It worked a treat and it even got rid of the odd flea that he had from the dog’s (treated them at the same time). I would like to say to give this a go first, BUT I CAN’T – you’ve already applied an application of another flea treatment and too much can make your bun sick, even kill it (sorry, but it’s true) so please DON’T apply anymore. Under the circumstances I would seek vet assistance, let them diagnose it and treat it accordantly. If it is mites, ‘next’ time try the Revolution (for puppies and kittens), I always have it on hand now – I’ve treated Henry 3 x’s.
PLEASE DON’T APPLY ANYMORE. Let us know how you go Pearl.