I Have Concern For A Special Needs Teen. He Has

I have concern for a special needs teen. He has trisomi 1. He constantly shakes his headback and forth. Its more of a cconscious thing. He controls it. I. Believe its a comfort to him. At night its accompanied with noise. My concern is weather it can be damaging. This is from a marriage that I recently left. And any concerns I have for him are ignored. I believe the habit came from toddler age. Long story. But that it can be broken.