See your doctor, go to a Orthopedic guy, sports medicine. Get a MRI, see if you have a rip or something like that.
I recently was in a wreck, the Naturapath I hired, fixed my neck, back pain (sort of the massuse re-injured me). The odd thing is my knee that ached all the time, stopped hurting me.
I had surgery for a torn ligament, the doctor could not find the rip, he just cleaned out the joint and flushed it. Exactly a year minus one day, I tore it loose again. I can not have another MRI because of the computer in my shoulder, so I am just dealing with it.
I have a brace with all the bells and whistles I use when the joint feels really loose (ripping feel when I walk, feels like it is going to give out totally). I am able to walk quite well in the brace, it did require practice and a stuborn streak. I would not use it on the trail for an extened hike. I do wear it for climbing around the Columbia River Gorge for some day hikes.
Experiment on what works for you, different type of hammock, padding, elevation, cold pack on the knee at bed time. I have done that with something warm on my tummy, works great fools the body into thinking it is warm.
I do sometimes use hiking poles they help, however, I dislike depending on them at my age. I do not want them to become a need instead of a like.
It is really better to find out what is happening with your knee. Having a rescue team come in and get you is bad form, to be avoided.
I was taking some anti-inflamitory meds before a trip, however I have discontinued that practice, before it became a habit. Pain meds only work for a while, and can have nasty side effects.