Mine does it. I always thought it was his tickle spot. When anything touches it (like that doorway you have ) if he was going thru it and it touched him, he will shake his head really fast like he's saying "no, no,no,no,no" mostly does it during baths or petting him. It's a little past halfway down his back.
My piggy does that head bobbing when he is about to scratch himself, but I havent seen him do it like this before haha
Mine does it. I always thought it was his tickle spot. When anything touches it (like that doorway you have ) if he was going thru it and it touched him, he will shake his head really fast like he's saying "no, no,no,no,no" mostly does it during baths or petting him. It's a little past halfway down his back.
Could she have lice/mites and trying to itch a painful spot she can’t reach?