I have serve pain from my lower back down my right side through my hip and to my knee. It's agony to walk and I've been taking painkillers but no help?

Serve pain? You've skipped the most important point, which is the CAUSE of the pain. It's a basic principle of medicine (& automobile repair): You can't fix it if you don't know what's broken. This could be a nerve, musculotendinous OR joint problem, or even a fracture. They taught me in med school never to do a physical exam over the telephone. Same thing re the Web. See a doctor & get a diagnosis.