Okay, so here's my story...

I'm playing in an orchestra. I've done this a few times, and I'm not too concerned. But I'm also doing a violin piece along with a piano accompanist. I'm stressing out right now! It was a last minute suggestion by my friend. It's in 2-3 weeks, and I can't say no because everybody wants me to do it, and I want to do it too, but I get so nervous.

I have played the piece well enough that if I make a mistake I can just go on, but in the the last measure, I have a quick chord (E {D String}, C# {A String}, and A {E String}/A major chord) right at the end, and sometimes when I play the chord I misplace my fingers and it sounds like a really bad squeak. I've been practicing everyday and I guess I'm getting the hang of it. I'm just so scared.
Do you guys have any advice for stage fright and how to get rid of it? I have a really bad case of stage fright and every time before I get ready to play, my heart beats fast, and I tremble. I know it sounds weird, but I really need advice for my stage fright
I know this isn't a forum for instruments, but I don't know where else to ask.

Thank you in advance.