Hi Every Morning I Wake Up With A Dull Pain

Hi every morning I wake up with a dull pain in one spot on my back. It is not super painful and it probably is about the size of my fist. When I breathe in deep in gets worse but the pain only lasts about 15 minutes and then is gone usually the rest of the day. I have never had this before last month but now it is pretty regular. I am 22 and pretty good shape. Non smoker. Any idea?