My knees are wonky, not sure exactly why - might be too much strain without a proper base, might be age, might be previous (small) injuries. I use neoprene knee-sleeve thingies (I have no idea whatsoever about a proper English term for these) during Judo practice and do composite movement weight training following the SL 5x5 program. In my experience this helps. See a doc, or a sports oriented physio therapist of some sort. A general practitioner might not have the knowledge you're after - a physio rehab person is a fairly likely bet. Ask around - your fellow athletes might have a contact or three they trust.
Regards, and good luck,
Mike Robertson knows his stuff when it comes to knees. This is a good place to start. http://www.t-nation.com/free_online_...DD-mcd01.hydra