Can sleeping on a couch cause back pain?

My basement, where my bedroom is, is being remodeled. I've only been home a few days this summer and am about to leave again, so I didn't think it would be a big deal. But now my back hurts to the point where I can hardly move! This is a relatively new and incredibly comfortable couch, my pillow is flat on the surface, and I'm not sleeping in an abnormal position. Believe me, if we had the space, I would drag my mattress somewhere and sleep on it to avoid this pain!