Well, while I confess I am not the most knowledgeable person to ask about BDSM, if there are limits of ANY type in ANY sort of relationship, they should be strictly observed. Him going beyond those boundaries isn't, in my opinion, so much a master/sub issue as it is a plain relationship issue.

I'd tell you that if he cannot respect your "no," specifically in a matter such as this, that might be a sign that you need to reevaluate your standing with him. "No" should be an instantly respected thing within the bedroom. To violate that is a major red flag to me.

I am sorry this happened to you. If I can be of any help or if you want to talk about it if it would help, don't hesitate for a second to PM me. I'm an open ear.

My best and hugs,
Harley