Awaiting vet appt tomorrow

Hello fellow animal lovers. My 7yr old terrier/chihuahua who I've had since 6weeks, mix has been experiencing ear discomfort over the last few weeks. We live in SW Arizona, and he only has access to a fenced in grassy/soil yard, daily walks, and eats Open Farm Small Breed food. Up to date in all vaccs.

My job has a large animal vet that comes by and he took a look at my dog and told me it was most likely a yeast buildup, and directed me to some otc drops. We tried it for a few days and it seemed to help take the itchy away.

Last night he has woken me up by violently shaking his head, as dogs do when theyre wet or drying off, and also digging at his ears with his paws and yelping in pain. Ive checked with my flashlight in his ear and it looks red, and angry.

We made an appt with his actual vet in town and are awaiting this but anxiously trying to make him comfortable too in the meantime. Warm compress seem to help, but has anyone else dealt with this? Or could recommend any quick remedy while we wait for our appt tomorrow?

Thanks in advance ♡♡♡