An interesting personal account of how anxiety can manifest through the formation of 'bad habits'.
Our culture so greatly stigmatizes aberrant behaviors that most of us who have them—no matter how minor or concealable—work overtime to keep anyone from noticing. We can’t risk being perceived as unprofessional or ill or in need of assistance or supervision.
http://www.theestablishment.co/2016/03/18/painfully-picky-the-physical-manifestations-of-anxiety/