Noting that I applaud the introspection: He was embarrassed for thinking he sounded stupid whereas I think he should have be embarrassed for seeming like a jerk.
But anyone who would rush to judge someone so harshly is revealing themselves as the bad person. A little compassion is all that is necessary to see that you meant well.
Take pride in having gotten on stage and put yourself out there. You tried something that would scare most people to death. And you did quite well. Plenty of people like myself have nothing but respect for you and don't think you're a jerk.