Sharp pain on side of ribs under arm pit, sometimes moves back near shoulder blades?

Costochondritis? Superficial chest wall pain in young women is very common. If you press gently on the painful area and find a spot that's tender to the touch -- but not red, hot, or swollen -- that might be it. See an md if you have fever, cough, weight loss, bloody sputum, wheezing, or shortness of breath. Costochondritis is harmless and often due to stress. See the mayoclinic.Com discussion on this topic.