I have kidney disease i am on dailysis my lower back hurts only when i lay on that side i took x-ray and the dr said he couldn't find anything wrong?

Infection: Do you still make urine then kidney can have infection suggest urine analysis and culture.

Is it chronic pain?: Chronic lower back pain is a common problem seen in many in-center hemodialysis patients, often related to sitting in those uncomfortable chairs for 4 hours or so. If this describes you, try using a firm pillow or folded blanket to support your lower back during treatments. Also, ask your nephrologist how well-controlled your mineral/bone labs are. High PTH levels could result in bone pain.