8 m/o shaking head from side to side when getting diaper changes?

so I thought maybe this was totally normal, but I've noticed whenever my 8 month old gets diaper changes now (and doesn't want to) he will shake his head from side to side as he cries very repetitively(and try to flip over as well). When I looked it up, it said it could either be an ear infection, just a new learned behavior, or a sign of autism. Now I'm worried.

Has anyone elses baby just picked up shaking their head from side to side when upset?? Or should I be more concerned.

He hasn't really shown any other early signs except for when he was younger he didn't like being out and about. If anything though, he has gotten more used to and likes going out to stores and such.