What Causes Severe Pain In The Buttocks?

Several days ago, I moved just right & instantly felt a sharp pain. Not in my back but in more in my left buttock. It feels like something twisted & is creating immense pain. The best description would be similar to a bag of air used for shipping fragile items is twisted so tight it s ready to burst but just keeps increasing in pain. At first I thought I just tweaked my back & it d go away or at least lessen with heat, excedrine, ice, laying down as often as possible. Nothing has helped even slightly decrease the pain. In fact, the pain has been increasing to the point that I can t sit down, can hardly walk (sliding my left food about 2-3 inches forward at a time is about all I can stand to do), & doing anything with pressure on my left side is excruciating. Will this go away eventually on it s own? Is there a remedy I haven t tried that would help me? Do I need to go to the doctor? Should I just push through the pain & see if I can burst the (4-5 it feels like I have) bubble to get relief?