Could be Sciatica, I have that on left side too, did you do anything recently to strain this muscle? Also, does the pain run down your leg too? Nothing really helps that, mine got so bad I asked my doctor for pain relief and he prescribed me Vicoden, but I am to take it only when it is acting up really bad, not everday. It does help give me relief. Another thing you can try is Ice pack on the area.
