Knee pain around patella. Routine.

Hi, i am a regular jogger and run around 7-8 kms 5 days a week and during weekend i play either soccer or cricket. From past few months i have been suffering from pain in my knee specially around patella in my right knee. Even sometimes i had problem climbing the stairs. This happens specially after weekend games. I did consult physiotherapist for few weeks and he recommended some knee exercise along with some vitamin c supplement. After few weeks it improved but pain didn't go away completely. As long as i walk it feels okay but the moment i start sprint or play soccer. Right after the game i feel the pain in my knee. I also consulted a orthopedic and he too suggested some vitamin supplement like mobikart-d or orthoboon I have stopped playing weekend games and also stopped jogging from past 3-4 months. I now only brisk walk for 10 km. But i am not getting rid of the pain. Any suggestion would be a great help. I badly want to get back to my earlier routine.