Hi, I've googled this and it seems to be something older babies do, my twins are 12 months (10 corrected) and my son keeps hitting himself repeatedly at the side of his head, like the temple area. It started as smacking himself and now he properly hits himself with the heel of his hand at both sides. He's also done it with a toy a few times til his head is RED.
I've shouted no, I've held his hand/arm, I've done very sad face and pretend cried, I've ignored it, but he doesn't stop! I like to think I give them lots of attention, but he does tend to do it when he's in his highchair (does it other times too, but more so in highchair).
also, maybe relevant, maybe not, he scratches in his ears til they bleed. Not the canal part, the inside of the outer ear if that makes sense (??). This is mainly before bedtime though so I think it's common? I really don't think he has ear ache cos he's fine in all other ways, but should I take him to our GP to check because of these two things?