From your description of the complaint it looks like what you said…patellar Chondromalacia or early damage to the undersurface of the Knee cap. Since you already have the x-rays please post them here so that we can have a look. Also, I would suggest that you take a blood test for
vitamin D3.
If the pain interferes in your day to day activities use of a mild painkiller should suffice
Next Steps
Please see a good physiotherapist in your area who will guide you for knee strengthening exercises
Health Tips
Avoid sitting square legged on the floor and avoid squatting fully or the Indian toilet position
Ice fomentation usually helps.
Avoid local applications/massages etc