Sciatic problem. The right doctor?

Have pain in lower back on one side. The pain increases before sleep and in the morning. Fell better if I walk a bit but walking causes a limp. Cannot walk without limping. Forget running. The pain is felt from the lower back through my whole right leg. Consulted two doctors. X rays show no problem in spine. Doctor advised physiotherapy with IFT. did it for the advised duration but no effect. Using ice and hot packs give a slight and temporary relief. Suffering from the problem from more than a year. Please advise something permanent. It's starting to agent my morale and I have started gaining weight. From 78kgs to 93kgs in a year. Consulted an orthopedist earlier. Have i consulted the right doctor? Also have not been to a gym in 4yrs and no major sports played. So i guess it's not a sports injury. PLEASE HELP!!