Head vibrating when stroked?

Whenever I stroke from top to tail on my beardie, she flushes orange, lowers her head with her eyes shut and starts super slowly waving her arms. I always take it as a sign that she likes being pet. However, for the past few days, whenever I stroke her the same way, she still stays orange, lowers her head and waves, but the first few strikes it almost looks like her head vibrates. I’ve never seen her do this before, at first I thought she was bobbing up and down super fast but she doesn’t go black or anything, so I don’t think she means it to be aggressive.

I’m concerned about a calcium deficiency because she hasn’t been eating bugs or veg properly for weeks now, I’ve posted about this multiple times before. No matter what I do, she won’t eat, and I’m worried this head vibrating is a sign she’s deficient in something even though she’s only done it twice and only when I stroke her. I’ve never seen her do it any other time. I did also get my nails done recently and wondered whether it might be some kind of reaction to the bright sparkles of the paint - I know beardies can be sometimes react to the colour/patterns of the clothes you wear!

Hi there, it sounds like she actually doesn't like it. When they arm wave and do a slow head bob it's a sign of submission, so that means she may be stressed at that point. Some beardies really just don't like it, especially stroking the top of the head where the 3rd eye [ parietal eye ] is.