Bad bed or not right for me?

This was too firm for me when purchased but part of a compromise. The first year was not too bad. My 5'6" 140 lb partner loved it. At the time I was 5'3" and 180 lbs. After that first year I began to have very bad lower back pain if I was in the bed for more than 7 hours. By the end of the second year I was also having severe shoulder, arm, and hand pain. If I ever slept more than 8 hours my entire body would ache. I ended up spending most of my nights sleeping on my couch. I am looking for a new bed now and hope that I can find something that does not cause me as much pain.