Shortness of breath, excessive yawning, and back pain?

For about two weeks I've been having a shortness of breath resulting in excessive yawning to take breaths. But every time this happens I have pain in my upper back. I've woken up a couple times in the middle of the night and have to sit up gasping for air (which was quite scary). I'm an active 16 year old and in shape. Everything I've found so far says obesity, heart attack, aortic dissection, or anxiety. I'm not obese, I'm too young for a heart attack or aortic dissection (right?) and I have nothing in my life causing an anxiety or stress whatsoever, can anyone help me out with what might be wring and what to do?