Hi Tmullen,
SO sorry to hear that you are in so much pain right now!

I noticed that you are only 16 - I really hate to hear about anyone having to deal with this pain but especially teens and kids as I know how hard it can be and how much life you miss out on because of it (i'm 14 - was 12 when I initially developed RSD)!
I too have the extreme knee pain that you mentioned. I have RSD in my left leg and both arms. I always had knee pain since developing RSD however, it got worse after my PT's used a splint during Physical Therapy to try and correct the Dystonia in my foot and leg. I think they somehow managed to stretch my leg too much and damaged it.
When I mentioned the knee pain to them, they said it sounded a lot like Femoral Patella but that I'd need to see an Orthopaedic Doctor to get it diagnosed and treated properly. I haven't had an appointment with my PTs since then as I have been ill and one of them has swine flu but we are going to mention it when I see them next.
When you press down on my knee, you can also feel some creaking in it. My PTs said that it felt (and sounded) like I had some frogs in it - sounds strange I know but it does when you think about it lol!!
Has anyone ever mentioned Arthritis to you? When I was diagnosed with RSD, my Doctor said that my bloody work showed I had Rheumatoid Arthritis. I also have Hypermobility Syndrome where my joints bend more than in a normal person and am more prone to injuries and pain conditions.
I hope you feel better soon and i'm here if you ever need/want to talk!
Alison