Hi i am Dr Ahmed Aly thanks for using HealthcareMagic site , I had gone through your question and understand your concerns .. In my opinion that could be a kind of sciatica due to nerve compression or it could be a muscular spasm or sprain . If your X ray was free from any bone injuries then it is either a muscular spasm or a nerve injury . i recommend painkillers like advil tab when needed , hot massages with topical gels , muscle relaxants , B12 vitamin supplements will be effective for most of cases . Physiotherapy sessions with a chiropractor , spinal straightening exercises , massages and even yoga are very effective in such cases . Try to avoid heavy lifting , over weight , vigorous movements , bad sleeping or sitting postures and try to relax your back muscles from any overexertion . If pain persist i recommend MRI to rule out any spinal injuries or disc herniation and visit your neurologist for proper evaluation and management . Please click and consider a 5 star rating with some positive feedback if the information was helpful. Wish you good health, Any further clarifications feel free to ask.