My first pub speaking experience: Fifth grade, running for school president, I was by FAR the least popular kid (to the point of being actively hated) that school had ever seen, being the child of the only two hippies in a very white, very rich, very conservative town, and hey, they'd always told me how smart and creative I was, so I didn't prepare anything, and I just . . . stood . . . there. Couldn't open my mouth to save my life.
And you'd think that would make me massively phobic, but instead I got really involved in drama and have not had a problem since. Never get nervous or stage fright, except right before I go onstage, I think I have to go to the little girl's room, even if I don't at all. Go figure.