Replying to How do I fix my knee issues...?

So were on christmas break from school and my local was open for 2 weeks straight 10 to 10. I was there every day well day skiing park except for one day. I dont ski to hard but it's still alot. And in the past few days I have had a really bad knee pain when I put pressure on it or when I sit down for prolonged amounts of times. I'm only 13 so I dont think I should be having knee pains yet haha. Anybody know of something like this and how to help it??