Sometimes i experience sharp pain run through my right leg and i barely can stand on my right leg. it has been many years. is it sciatic nerve pain?

Most likely!: Have yourself seen by an orthopod to get investigated as to the cause of your symptoms, as its probably not serious, but it isn't normal to have this going for years. L spine xrays, MRI as deemed necessary, alongwith a detailed hx, would help to diagnose it and then treated. Good luck.

It may be if it is -: Pain that radiates down the leg from the buttocks or back down the leg below the knee that is generally made worse with prolonged positioning or activity & better with rest. Sometimes it may be associated with numbness, tingling or weakness. The pain can vary in intensity & sometimes feel like an " electric shock." the pain can be a continuous one over the path of the leg or can skip areas.

Pinched Nerve: Sounds like you have a pinched nerve in your back or leg. I would suggest seeing a pain/spine specialist to evaluate you further to evaluate what level and what can be done to treat you. There are interventional treatments besides medications and surgeries that might reduce or eliminate the pain altogether.