Knee problems. I'm a gymnast?

Your best bet would be to go see a doctor about it. I think your knee cap may be too much to the inside. I'm telling you this from experience. I was in gymnastics for 8-9 years and am now a coach at the age of between 14-16. I had to quit because of my knees and back but mostly my knees. I have Osgood Schlatters Disease in both of my knees. In my left knee, my knee cap is too far to the inside, it's overused, and there is a third thing but I can't really remember it. I used to go to physical therapy, tried all kinds of braces, had a special taping thing I had to do that I got from physical therapy, and yet none of that works so I eventually had to quit or be at risk for surgery in the future. You should really just see a doctor. Hope this helps and all goes well!