Probably this is a very late reply but it might be of some use to you. Your symptoms are suggestive of initial stage of osteoarthritis
knee, a common age related degenerative condition.
Tab Hilin GM is a joint specific anti-inflammatory drug with side effects like diarrhoea
in rare cases. This will be useful in your case.
Other precautions like avoidance of frequent stair climbing, squatting and sitting with crossed legs will be helpful.
Use of commode for toileting will be helpful (as it avoids squatting).
Stretching of hamstring
muscles will help in prevention of knee joint deformities and strengthening of quadriceps muscles will improve your pain tolerability and endurance.
Daily walking will also help in maintaining endurance.