Changes in shape, fat, and muscle in the face and body

This change in the size of the face and neck, and the distribution of fat and muscle tissue, can sometimes be exacerbated by supplements, vitamins, or certain foods.
I feel like my neck is bent and my face is melting and losing volume. My jaw is pulled back, giving the impression that my face is very smaller from below. In addition to general fatigue, a feeling of muscle weakness that have weak inability to lift the body.

I'm not looking for medical advice, but any hypotheses about the cause of this condition?