I keep having short episodes (2-5 min) of sharp stabbing pain in my chest. It only hurts when my lungs are more than halfway full of air so I start to breathe quickly and shallow. Right before the episodes I get dizzy and feel like I'm not getting enough oxygen. The pain is very intense 9/10 on a scale of 1/10. It radiates to my back and my left elbow. After the episodes I feel very weak. This only happens and couple times a month but it is very scary and I'm worried it could signal something more serious.