It sounds to me like tardive dyskinesia. You should look it up and see what you think. TD is caused by anti-psychotic drugs and is sometimes permanent, but there are treatments for it. I would probably consider treatment, considering that it could happen at any time, and you could be more seriously injured. From what I understand, one of the key differences between tics and dystonic movements is that tics come with a compulsive urge to make the movements and a sense of relief after making them; dystonic movements are completely involuntary and random.