Back Pain: What to Do?

Icy Hot and invest in a massager! They make electric shock ones that can mimic stuff like kneading, pressing, etc. (like the settings on a massage chair) that can undo any pinched muscles or knots for pretty cheap. Either way, if it happens more frequently I'd look into seeing a chiropractor thats nearby and affordable for you so you can make sure everything is all adjusted.

Locate where exactly it hurts. What type of pain? Burning, Stabbing. Etc. ? Try ice or heat for now.