Numbness / Tingling in right hand (pinky/thumb)

I was kicked in the right forearm, which resulted in the forearm to be crushed between the persons foot and a metal desk.  There was immediate numbness and tingling and as the swelling increased, loss of function to the ring / pinky finger and thumb. Cleared with no fractures, and over a two week period the function to the fingers and hand have returned.  The initial shooting electric like pains I was feeling have subsided greatly and no I have numbness and tingling through the palm, pinky and ring finger and underside of the thumb.  I still have pain with flexion and extension of the wrist as well as any rotation of the wrist.  I also have a sensation like there is a "forcefield" around objects when I pick them up.  Most notable with smaller objects like, buttons, or paperclips.  I have had a nerve conduction study which has come back negative, and an MRI with results pending.  The accident was approximatly a month ago.My question is this:
If my nerve conduction study is negative, how is it that I am still having, what I would consider nerve ailments?  (Numbness and tingling / difficutly extending the thumb / pain with flexion and extension of the wrist / pain with wrist rotation)