Left side pain and numbness

I am 34 years old.  I have had lower back problem for a few years, but nothing major.  About a year ago I noticed my left leg was numb and in pain, along with my left arm on occasion.  I went to a chiropractor, but this helped only a little.  The numbness and pain began to increase on my left side along with feelings of fatigue.  I went to my MD who did blood work.  It came back okay except for low calcium.  I had an MRI done on my lower back around 6 months ago.  I was told I had a bulging disc which was causing the lower back pain and was probably causing a pinched nerve.  Since this time things have not improved.  My left arm, left side of my neck, left pinky finger, left hip, and left leg are in constant pain and/or numb.  I also am feeling very fatigued.  I was blaming my tiredness on working, but since school has let out for the summer I am still tired if not more so than when I was teaching.  Could all of this be caused by a pinched nerve?  Is there a possibility that it could be something else?