I'm so sorry to hear that you have been having some very difficult and scary times. When I read your post my heart dropped because I have been in that circumstance 2.5 years ago.
My CRPS started in the right hip and within a month the whole leg was affected from hip to toe. Within the first year the CRPS spread to my left leg and I too felt like my knees were hit with a baseball bat over and over. I was not diagnoised until last year so every dr said that it cant spread and the left leg was mirroring the right however when I saw one of the top specialist in Chicago at Rush University he tested both legs and confirmed both the left and the right have CRPS. I dont know how a dr could possibly think that this disease does not spread when both my legs are crazy looking as usually ice cold and purple which I thought was a dead give away. The one thing I have learned in the last 3.5 years of dealing with this is as follows:
1. Dont trust the nurses, the have F*** me over by always trying to be my Dr and not passing the messages on the Dr *the not passing messages has happened over a dozen times!
2. Keep calling to get the message thru to your Dr because the quiet patient is a patient that the Dr thinks is doing okay. Request to speak with the Dr and call every 30minutes if needed.

It may seem like I'm telling you to be rude but really you are paying for your Dr's care and anything less is unexceptable. You should be able to talk to the Dr on the phone in the least.

I hope that your left knee is not hurting because of spreading but if you have not taken a direct injury to the knee recently then what else could it be? Good luck and keep us posted as to how you are doing. You are in my thoughts and prayers.
Sarah