There is a dull pain in my left knee. It feels like its a ring of pain around my kneecap...

I was into Parkour for a while, then stopped because of knee fears/small pain. My right knee doesn't hurt, but there are small pops or clicks at random times in both knees.

There is normally no pain, but recently its been more constant. This has spurred me to go see a doctor, but until then I was wondering if it sounds serious to anyone?

Joint problems always scare the **** out of me, and im afraid that ive damaged my my knee by jumping around. I honestly hope its not something that cant be fixed/healed/whatever, because I feel like im way too young to be complaining about my knees hurting :P

Thanks for any info before I see the Dr. Man.