Well, the first knee could be causing pain due to a cartilage, ligament or a meniscus injury since this happened on using the
knee joint. However now since multiple
joints are involved, it goes more in favor of associated arthritis. It can be osteoarthritis, rheumatoid arthritis, or even reactive arthritis. You would need some tests and X-rays of the joints to diagnose this. The pain in the joints can also be due to overweight, hypothyroidism and diabetes.
Hope this helps.