Costochondritis?

About several months ago, my lower left rib cage area begin hurting at work (I sit in front of a computer all day), with the symptom of a very sharp pain (no physical activity per say that would have led to this).  Since that time, I've had bouts of dull ache in that area, along with occassional shortness of breath, primarily when walking up steep inclines (relatively no problems on daily treadmill walk of about two miles).

I've come across this illness and wanted to get a sense as to whether you thought this might apply.  I've felt this way for several months now.

[National Jewish]

Costochondritis is swelling of the cartilage that connects the ribs to the front of the chest.  This causes a dull aching pain along the front of the chest that is felt more when touched.  This is treated with rest and the use of non-steroidal anti-inflammatory drugs (NSAID) like ibuprofen.
Based on what you have described costochondritis may apply to you.  Please check with your doctor to know for sure.  It is possible for costochondritis to be worsened by working at the computer with poor posture.