Pupper has an ear infection

Back story-

We adopted her and I switched her to a sensitive skin salmon recipe, she started to lose a bit of fur and I had added omegas 3s from salmon, and fur loss got worse. Switched her to a non-salmon diet and her fur is growing back, but she is now experiencing and ear infection in her left ear as of 3 days ago, with noticeable symptoms (no fluid discharge).

All of my local vets are booked out weeks til end of December, early January. Is there anything we can do to help? Warm compress? Of course I don’t want to put anything IN the ear, but want to relieve her a little til we can get in. Have been giving Benadryl once a day for the last two days but don’t want to continue for extended periods.