Being an MC for an event. I’m so stressed and depressed.

Being an MC for an event. I’m so stressed and depressed. I’ve been chosen to be MC for an event. We had a rehearsal and it went terribly wrong. I feel ashamed of myself. I don’t think anyone knows I stutter. I’m so anxious, stressed, and nervous to the point I can’t eat. When I practice with myself, I don’t stutter at all. But when I have to speak in front of people, it’s like I forgot how to breathe and the words can’t come out. I’m feeling so lost thinking of how much more confident I’ll be if I weren’t stuttering. I would’ve landed so many jobs and would’ve felt less inadequate. I’m having a mental breakdown. Does any one have any tips or any words of encouragement. I really do need these right now.