With my first, that was exactly how it felt. A bad backache that kept coming and going away. Finally DH starting timing and they were coming regularly. In my case, though, it was a 30 hour labor that ended with healthy babe born with episiotomy and vaccuum suction, cause he was positioned backward. My sincere hope that all that intervention will not be needed for you!!!
Dawn, mom to 3 great kids and fishnoodles cloth diapers