Greetings, sorry about the pain. This is no way related to your previous illness. Your knee pain is related to poor lubrication of knee joint, meaning not moving knee enough.
Next Steps
see a physio and get treatment for knee pain. trigger point therapy, massage and exercise are best approach a physio should be doing. you will also learn how to better manage knee and these approaches will help knee well lubricated.
Health Tips
medicine is of no use at any stage. if any questions do let me know.