This is probably obvious, but if you can, play with the music. My orchestra director had told a story of a girl who memorized their violin solo front to back flawlessly, but when it came time for the actual performance, they had forgotten a chunk of the music and the orchestra had to improv for her.
Other than that, don't stress too much over it. Just take a deep breath, try to relax, and play. If anything, maybe warm up with some finger exercises if you can. If you practiced well enough for the teacher to praise you, you should be fine.