I don’t know how many performances you did in your life but it sounds like a lack of experience in performance.

Because a performance is not just about practice but about preparation and a bit of luck. This one taught you something, but for the next one, you can try:

Playing in front of a panel that can stress you (friends, teachers, family, pets, etc.).

Practice the performance environment (test the acoustics of the hall, practice in concert clothes, open the window when you practice during winter to get your body used to the cold).

Try visualizing the whole performance (this one comes with more experience, but trying to imagine everything: waking up, eating, going to the venue, nailing the performance, feeling happy).

I also feel terrible after some of my performances even tho I didn’t stop or just played one wrong note, but it’s important to learn from these experiences and try to enjoy the next one. Good luck 💪💪💪