Years and years of dealing with an oft broken body....mine! But do see somebody so you can find out what back component has been injured causing the muscle to spasm like that. For example, if a disc injury, the muscle spasms, literally trying to pull the vertebrae off the damaged disc, providing some relief for it. Your doctor will be able to tell you what is going on and help you prevent further injury. Rest and meds should get the muscle to stop spasming and whatever back component has been injured should calm back down again. But you really want to know what back component has gone bonkers on you so you can prevent further injury and make sure you have controlled this one.