With the information provided it's hard to know.
Grinding sound could be beak grinding which is a happy sound for many birds.
Shaking the head could be a sign of vomiting, or something not feeling right in the ears, mouth, or nose.
How old is your bird? How long have you had them? How long has this been going on? Can you get a video?
How to post videos to comments and threads The only way to post videos in your comments or threads is to paste the URL of the video uploaded to a file hosting site like Youtube, Facebook (public videos only), Vimeo etc. You cannot upload any videos directly onto Avian Avenue. Here is a link...
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