Losing balance, head goes crazy.
Thanks for the information! I'll definitely add those vitamins. :) Another symptom is that she also stands with her head down, and wings almost touching the floor with eyes closed while standing but she perks up around any food.
Here is the video of the head shaking, it starts around 35 seconds in:
Its a constant thing that happens, not just when she's eating. This video was taken after I got her to wake up from being limp.