Issues with ACL reconstruction/meniscectomy rehab

[Lizn8r]

I'm a 47 year-old female who is 5 weeks post-op from allograft ACL reconstruction and 25% medial meniscus removal on my left knee. I have been in PT 3X/wk since day 10 and am very proactive (meaning I really do all my exercises at home on my off-PT days) in my rehab, however I have an issue that is really becoming problematic.
First, my history - the ACL tear was a 10 year-old sports injury that was originally misdiagnosed as a Grade I sprain with signs of arthritic degenerative disease. The medial meniscus damage was due to the increasing instability of my knee over time, and the pain from it is the main reason I sought more attention. During the 10 years since injury, I went from being moderately active to basically a couch potato due to the pain and (what I know now was) instability of my knee. When I found out my knee could be fixed, I jumped at the chance.
The problem I am having started early as fairly severe pain on the lateral side of my kneecap, along with what can only be described as a "shifting" of my kneecap when my knee was being extended after flexing about 80 to 90 degrees. Riding a stationary bike was painful as my kneecap would 'shift' every revolution. My PT and PTA, who are both fantastic at their job, agreed that it was a patellar tracking problem. Taping my kneecap was ineffective as the tape would not stick to my skin. I was limited to minimal exercises and they applied soft tissue massage and laser therapy at the site of pain for a couple of sessions. I chose to try to ignore the pain and continue on with the work on my personal stationary bike along with all the other prescribed exercises. One home workout produced a loud crack and flash of intense lateral pain while I was on the bike, but the pain eased and I continued. After that crack, the pain subsided enough to continue on with PT rehab. My OS released me from the Donjoy TROM brace at week 4.5 (I told him about the issues I had and the PT's had also given him a report, but he didn't think it was a major problem), and we started in with more weight-bearing exercises like squats, balance, and steps, etc. I had minimal pain and no shift while I was doing the work, but later in the evening the lateral pain rolled in and got pretty severe. I also had 'icepick' type pain behind my kneecap. Ice and compression knocked both back some, but the next day I was pretty sore. That was yesterday. And now today back at PT I could no longer do the squats or steps without the lateral pain flaring up badly. As far as I can tell, my kneecap no longer shifts but that pain is almost unbearable. My PT's want to go back to soft tissue massage and back off on the weight-bearing stuff while they try to figure out whats going on and determine a course of action. I'm ridiculously frustrated ... I knew when I chose to have the surgery that the rehab time was going to be long and tough, and I am more than willing to go through it. But no one I have talked to who went through or is going through ACL rehab has had this problem, and my PTs seem stumped as well.
I apologize for the long post, but I wanted the whole history of my issue to be out there in case anyone else has seen or has had this same problem. Could anyone possibly shed some light on what's going on?

[mtcpt]

There are some questions... do you have full ROM? Ask your therapist this question. What is your strength like? How far out are you from surgery? Once these questions are answered, maybe I will have more feedback.