Back pain at 38 weeks

Hey ladies! I'm a FTM. For the past week ive been having weird back pain. It's mainly in the center of my back and sometimes sends shooting sharp pain down my back, making it hard to sit up. When my back pain happens, it's constant and lasts for an hour or so. Then it's done for the day, which is why I haven't talked to my doctor about it. It's nothing timeable. I've only had Braxton Hicks up until this point. Was wondering if any of you guys have experienced something like this? Thanks!