I played flute in band, marching and symphonic, and I played piano in private lessons.
It can be nerve wrecking performing in front of people...it's certainly easier when there are 150 other people on stage or on the field with you!
But even so, like, then, sometimes, you're not just nervous for you, you're nervous for everyone! If another person messes up...then...eh...doesn't look good on you either ;P
But in any case, the best advice any music person will tell you, is to PRACTICE.
Knowing the music is the biggest step to confidence on stage. No matter what people say, it IS possible to play a piece perfectly, and it always always takes practice.
If you really know your music, then you can just trust it. If you have a performance and you're really really nervous, just keep going over the music.
Put your faith in the music and it will save you
