Knee issues! Help please?

So I'm a 15 year old Highland dancer. I compete at the championship lever, so I'm constantly practicing for an hour per day, every day. For those of you who don't know what high dance is, it's a high impact kinda of dance in which you're always jumping. A while ago my knee started hurting. It was a VERY sharp excruciating pain that throbbed whenever i jumped on it. It was only my right knee, and it ranged from the inner to lower part of my knee cap. I went to the clinic, and the doctor said it MIGHT be damaged cartilage. He never gave me a solid answer. Now it's getting better, but when I do i split high-cut (Jump off one leg, doing the splits in the air, landing on one leg, with the other on your calf muscle) it feels extremely awkward/ weak to land on. I have a dance competition next in 2 weeks, and I was wondering if there was any exercises I could do to strengthen it! Also, does it sound like a cartilage problem? Tendon/ ligament issue? Thanks =]