What Causes Discomfort In Left Hip And Thigh Area?

Hi, For a while I ve been experience slight discomfort in my left hip/thigh area when laying or standing in certain ways. However, when I got back from work today, I took a quick nap, and when I went to stand up, there was a pain so intense radiating from my hip down the back of my thighs that I couldn t take a step. It was mostly on the left side, but it hurt enough on the right that I couldn t step with that leg either. It faded if I stood completely still, but the moment I tried to move it came back. I crawled to my desk and took 500mg of Naproxin, and about 10 minutes after that the pain had faded almost completely. This is the first time I ve had such a sudden, blinding pain. I am a 20 year old female.