Sounds like you have Sciatica! check the following
Top 3 Exercises for Sciatica and Pinched Nerve
https://www.youtube.com/watch?v=htgyPKNHUls&feature=related
Your hip is out of alingment, you need to see a chiropractor, have an x-ray of the area and then get a good treatment, you will be surprised at how fast the pain clears up.