If you make a mistake, that means you are wrong and doing something different from the way it is intended to be. But that isn't a bad thing if you use the mistake as a tool for learning. In performance, it's important to make confident mistakes vs being timid and shy.

When you are shy, or trying to "hide" your mistakes it's a lot harder to see exactly what mistake you're making. This makes it harder to fix.

It is almost like you're asking permission to perform. You might be saying to yourself: "Is this right?", "Is this ok?", or "I hope nobody sees me right now because I have no idea what I'm doing."

Since you don't want to be wrong, you will try to hide your mistakes for as long as possible hoping to save yourself from being embarrassed, but an ensemble is only as great as it's weakest member.

So do your best to perform with confidence and go all in on what you think you're supposed to do. Do everything proudly with the best of your ability and be as self aware as possible with the parts of your performance you aren't comfortable with. Ask questions, write down your mistakes, and work on those things in your personal practice time. 

Remember, the only bad mistake is the one you don't learn from!