MacBook Laptop CD Drive Won't Recognize Any Disc or Eject

My MacBook suddenly will not recognize any disc I insert. Blank CD's won't open itunes. Prerecorded CD's & DVD's won't play. I can't burn discs. Then the discs will not eject until I restart computer while holding down eject button. I hear the sounds of the discs being inserted at first, then it just stops. No disc icons will appear on desktop either. Can't afford an expensive repair job. Can I fix it myself? Thank you! - Julie P.S. This happened right after I downloaded yet another new version of itunes -- not sure if it's related, but also can't play DVD's, so perhaps not.