Got humiliated in front of my cl. How do I deal with this?

I recently joined a consulting firm and went through a few weeks of initial training. In this time, during one of the modules, I volunteered to go up to the head of the cl for a role play exercise and was completely humiliated -- the person doing the role was acting very tough and I started stuttering in front of the whole (I have a stutter in my speech but it was just even more exaggerated when under pressure) and couldn't articulate my thoughts well. In the end, I was completely unsuccessful in the role play. I'm extremely embarrased about this and could feel that I was being treated differently from everyone else after this incident -- like they suddenly didn't have respect for me anymore. How do I get their trust/respect back? How do I resist the feeling of hiding under a rock?