From someone who's been there...
I can totally understand that little girl. I've been on stage in front of people many times, yet I still feel that nauseous feeling in the pit of my stomach when I do get up.
I don't blame her for going all Carrie on them. XD I have wanted to do that many times. But, in the end, all you can do is try your best. If you mess up, run with it. I've fallen on stage, I've slipped, I've forgotten lines, I've broken props, and it still never ceases to amaze me how much any actor needs improv.