[PokerintheI]

Go to a chiropractor. Get a referral from someone, preferably a chiropractor that doesn't think that they can cure the flu and cancer through spinal manipulations.

Having something "off" in your back and making a sudden or straining movement is a good way to end up with problems like you describe. A good chiro can put your spine and hips back where they should be. You will still have the current flare up, but at least you are less likely to aggravate it.

As an extra point, once this goes away, make sure you are including a decent amount of both lower and upper abdominal exercises in your workout. The abdominal muscles are heavily involved in keeping everything in line in your lower and mid back.