Am I doing something wrong if the front edge of the guitar digs into my right arm just above the elbow and makes it sore? Or is it just a question of a short arm versus a big guitar?
This happens to me with one of my guitars, but not with the other. The difference? The thickness of the guitar at the big end, and the one is only about 1/2" thicker than the other. I suspect your problem is a combination of arm length and how far away from you the guitar is. A thinner instrument would probably feel better.