I disagree about going to HR. They will not keep it confidential, and most likely will then work with this arsehole to take you out. HR is there to protect the company and protect it's managers. They are NOT there to protect Reps. In smaller companies I guarantee you they will tell him everything you said. It sucks, but it is what it is.
I would suggest you document everything on your own.
What happened?
When? Time and date
Witnesses? Other Region Members hear it or see it?
Any written questionable material showing you are being treated differently.
Lastly, if you are serious about protecting yourself you need to consult an attorney. They will give you an initial consult and then inform you whether it is worth it to pursue. If they feel you have a case they will help you document it. Good luck
