Ok, my right knee , i am getting a pain under my knee cap, it hurts alot when i walk with my right foot but i do not get any pain when i limp and walk with my left foot, in other words when i do not use my right foot, i feel now and then like a strong of pain pulling right around my knee, when i rub it it feels a little better, what is wrong? can you help pleasE! i am 17 years and i exercise using the treadmill!