if you have a good coconut oil it couldn't hurt to try slathering a bit on the red and raw parts, and seeing as it's for the ear you don't have to worry about the dog always licking it away
and yeah I'd say the whole being restless and chewing things up could be related to this, like as if the pain is driving her nuts and she's blowing off some steam, assuming it's not a boredom/ lack of exercise thing
as for the actual cause, many factors could play a part so who knows... are you feeding a decent kibble? could be an allergy thing