May I ask how old you are?
Frustration is really common. And if you're a teenager, then all those lovely hormones surging through your system make the frustration that much worse. A teenage girl is like a bipolar diva going from extreme happiness to the depths of depression. Everyone talks to teenagers about "enjoying their youth", but honestly, I think it's one of the hardest times - emotionally - you'll have.
Having said that, you CAN work through it. Sometimes the best thing to do is to step back from the situation so that, emotionally, it's not affecting you as much. Realistically, you'll still have to get up on the beam and do your routines. But give yourself permission to NOT be perfect. To miss the skill. Find the fun in it again. Wear a fake mustache in practice. Have a friend video tape your routine and then use a video tool to draw a tutu on yourself. Heck - maybe skip a practice or two and go to the movies or out with friends.
I think once you take the pressure off of yourself, you'll find the frustration goes too.