I do not really think that at 16 weeks one should expect the pain to be completely gone. My left knee has swollen up and hurt severely twice about five years apart, seemingly for no reason, at least no trauma.
The first time I saw my rheumy and after examining me and ordering xrays, he was not really worried about it and it did go away after 8-12 weeks. The second time was about five years later, same thing, swelling and pain, but no trauma. My PCP repeated the xrays (they looked the same), and suggested I see an orthopedist. I talked her into some oral steroids, and finally saw the orthopedist when I finished them and was taking OTC NSAIDs. He explained why they do MRIs and did not really think one was needed yet. He said there was one ligament that the MRI does not show, so even if the MRI were normal, I could have damaged that one ligament, and surgery to take a look see would be necessary. He did agree to watchful waiting. This time the pain and swelling lasted about 24 weeks total, but did go away, and it has been more than ten years since the last time it bothered me. I am a good bit older than you, I am 61, and have FMS which can alter my pain response (not the swelling though) while healing.
If you trust your healthcare providers, I would just do what they suggest.
What have all these specialists told you to do about the pain you are having? Can you avoid the situations that cause pain for awhile?
Take care, Annette