I'm not sure where you live or what the regulations for employment are in your place of residence. But I'm going to echo the exact same thing many others on this forum have suggested. Which is to find your human resource manager and a human rights tribunal and forward your complaint to them. If you're place of employment provides paid sick days you can take some time off under this provision given that you were blatantly discriminated against and it caused you grief. Do this while you sort the complaints to HR and contact any local stutter groups that may be able to get you in contact with human rights groups. What he did was outrageous and who gives a f*** that he's the supervisor of all the other supervisors, if he doesn't own the store he should be fired. If he does own the store f*** him again and his business should fail and he should go bankrupt so it will teach him a lesson. And most importantly don't let this affect your confidence. F*** that guy he's a real piece of s***.