It sounds like sciatica, or what we trainers like to call piriformis syndrome. The piriformis is a muscle in your low back near your sacrum which, when inflamed, aggrevates the sciatic nerve. It's generally caused by bad posture, poor seating habits, etc. If you stand with most of your weight on one leg while you stand, or if you drive for extended periods of time with your right leg doing all the work, it could cause this.
I'd actually recommend stretching and massage to reduce the inflamation of the piriformis.
Though it's possible to stretch this muscle yourself...

... I recommend having a personal trainer or sports doctor assist you with the stretch...

Hope this helps! Sciatica is no fun - the good news is it's relatively quick and easy and inexpensive to alleviate the pain :)