I have sharp, knife like pain in my left hip, any guesses?

I have sharp, knife like pain in my left hip. It usually occurs when I am laying down, on my side, or sitting "indian style". It also hurts if I spread my leg out to the left. (think of a woman in the missionary position, sorry best scenerio I could come up with, lol, also, btw, I am a guy) I also just noticed that my left hip pops when I turn my leg, but the right one won't. Bottom line it hurts, but not sure if it is something I should go to the doctor about. Anybody have any thoughts?