If your persistent knee pain is not attributable to soft tissue problems, then OA may be developing.
Cartilage has no pain sensors. The deep-seated knee ache you feel may originate in the bruised/inflamed bone marrow, the earliest indication that the adjacent cartilage may start breaking down next (refer to posts on 22-23 Jan '16).
Translating the "Fast & Furious" treatment strategy from the inflammatory arthritides (RA, PsA, SpA) to OA in the hope of preventing irreversible joint damage would entail getting an MRI done early, and "Treating-to-Target" any BME/BML if found. This may involve anti-resorptives as well as off-loading the joint till full resolution of the lesions is demonstrated on repeat MRI.
Common things occur commonly, and knee pain is as common as it comes. However, one shouldn't jump to the conclusion that it's Osteoarthritis. In fact, soft tissue issues like Jumper's Knee are far more common.
If you experience persistent knee pain, you should get it evaluated. Point tenderness often suggests a soft tissue (bursa, plica, fat pad, muscle, tendon, ligament) problem: quite easily treated. Ultrasound is an indispensable tool in diagnosis. Check out the attached images of my patellar tendinosis (under "comments" on my page)!
If you're wondering, I'm working on eccentric exercises and doing ESWT, but may resort to PRP if I get any more desperate and masochistic😲