recent lumbar fusion within last 2 wks. New pain.

I had a lumbar fusion 2 wks ago tomorrow. This morning I woke up with an entirely new pain after having a relatively good two post-op wks.  The only pain I have been experiencing last two wks seemed to be just healing pain. No sign of pain that brought me to surgery. I have screws and some type of new fake bone material replacing old bone that was removed.

I had major instability on my left side and alot of disc problems. This morning I woke up to a feeling on my left side of my back that resembles something that needed "cracked" or "popped" back into place. But in addition to that feeling is a very sharp pain in a very definite place. I wear my back brace religiously, as much as I hate it, but hate the feeling more of not having it on. When I showered this morning is when I really noticed it the most and has gotten worse as the day has gone by. I have not done any bending or walking yesterday more than any other day since surgery, so I am really at a loss as to what may be causing this. This feeling and pain, I say both because they are both very distinct feelings, are driving me crazy.  Any ideas? Anyone go through this? Thanks for your time.