My son has this same issue.. I took him in a few times incase he did have an ear infection bc honestly it's hard to tell with him.. For us it was fluid behind the ear drum.. It takes a week or two to go away...
His ears are also red and warm... Just keep an eye on it and like others said.. Look for allergies to foods and possibly an ear infection or tooth issues or teeth coming in

This is from an article I found online...

"Blushing isn't restricted to your face. You may also experience blushing in your ears, making them hot and red. Blushing often occurs in response to high emotions, such as anger or embarrassment. According to UAB Medicine, the blood vessels in your face and neck involuntarily dilate in response to high emotion, allowing blood to rush to the head and cause skin to turn red and feel warm. Younger people are more likely to blush than older people, and you are more prone to blushing if you have fair skin. If blushing becomes a chronic issue, you may develop social phobias related to your blushing. Therapy and some medications may help you learn how to control your emotions, thereby reducing your blush response."
https://www.livestrong.com/article/267469-what-...

Ear infection or fluid in ear, could need tubes.

If he has difficulty expressing emotion, it could just be blushing. You blush when you are embarrassed, angry, happy. So he could just be expressing emotion through his ears.

Thanks. I know my son won't ever let the doctors look in his ears so who knows what is going on in them. I also guess I need to start writing down what he eats so I can figure it out if it's an allergy.