Hi there ,
Welcome to Just answer !
Well, it seems like you are having what is called as Tic / Tic disorder , which is characterized by sudden , rapid , repetitive , purposeless involuntary movement/s or sounds . And this tic may have taken a form of a Compulsive habit as you find it as a relaxation act , which is characterisctic of a compulsion.
These tics are very common ,and usually do not require any treatment , as they get corrected by self regulation , but the problem arises when the tics become harmful to one's health , like it is happening in your case , as you have been inuring yourself due to this tic habit.
So, i suggest that you consult a psychologist and get yourself evaluated for tic disorder and on confirmation the psychologist shall be starting you on psychotherapy ( Counseling ) in the form of Habit reversal training ( HRT ) , which would help you to control this habit and overcome it without letting it cause any further damage and disfigurement to your body.
see the link below for better understanding ..
I hope this helps..
I wish you all the best..
Please press the ACCEPT button if you are satisfied with the answer as only then will i be credited for my service.