What are the other investigations done apart from x-ray?
Is there over-weight issue?
Are you diabetic?
Does your work entail weight lifting or prolonged standing?
With a young fellow of lean built, your significant pain warrants, further investigations. The first step is to get an MRI for the diagnosis. Taking analgesic medications will not take you any far, if the cause of the pain is not treated. But for that, cause needs to be ascertained and imaging like MRI will be able to tell you whether it is a disc disease, spondylosis, any spinal cord related issue or muscle and ligaments of the back or anything which is because of the combination of these structures.
The treatment is commenced after that and will entail, braces, analgesics, deep electrotherapy, back care in activities of daily living, and physical therapy.
Please read these resources for the causes and exercises of the backache;
Please feel free for your follow up questions.