I also used to bite my nails and cuticles. (still do a bit, but not damaging anymore)
Now I have this problem with my ears, they are itchy a lot, and sometimes I just cant stop scratching, to the point of bleeding, and infection.
I have been on a couple of different antidepressants in the last couple of years, (for depression, but most also work for ocd, or obsessive compulsive disorders) and they haven't helped the ear thing, so I think there is actually a problem, although allergy treatments haven't helped so I am thinking candida....but i digress
Sometimes I do this nervous habit that no one can see. I count my teeth with my tongue. And there is a systematic way I do it. I make a pattern. I do similar things with my fingers, tapping them in patterns. Also other muscles in my body.
Is this a compulsion, a habit or something else? honestly don't know. For the most part its not harmful, or keeping me from a fruitful life. I Just wish the ears would stop itching. I that I could stop bingeing. 10 days with out a binge!
fatmad