well im not a hairdresser however id say defo 2 weeks!! I had returned after a week to work but i was on light duties n just as well coz my left arm was still unable to move hardly. So be on the safe side n take 2 weeks minimum. You may be one of the lucky ones but you may not n hairdressing involves your arms in air all day which cant be good if your healing is slower than others.
Good luck
xx