Hey there
I work with dogs
I'm glad I stopped to read the comments
Wrap the dogs ears tight against the head but not too tight.
if a small dog, cut off the end of a stretchy sock and place it around the head like a head band.
Large dog you'll have to use something else.

There's a small vein that wraps around the ear
and when dogs shake their head a bunch it can rupture from repeated shaking.
Most likely from an ear infection?
Hydrogen peroxide in the ear canal if your dog does have one
and keep those ears tight to the head so when it shakes it's not making it worse.
That will help until you see the vet and have it drained.
it's not life threatening so if you're panicking, don't.
it's fixable.
A little benedryl will calm and make them sleepy if you need to keep them still won't hurt.
hope that helps.

Thank you so much. My poor guy has been misdiagnosed since June. Allergies. Allergy pills, prednisone and cephalexin. Last week I was itching like crazy. Mites. He has had mites all along. Makes me want to cry. He has patches of hair. He is a beautiful Portuguese Water Dog. He now looks like a homeless dog. Earlier I tried using a winter scarf to pull his ears down, not successful. He has an appt at 11:00 this morning. Yes with the vet that misdiagnosed. She should be glad I’m so forgiving. With me not sleeping for 3 nights I will have to control myself…hopefully.