I get a pain right in the middle of my back. The center of the curve. I never had this before I got…

I get a pain right in the middle of my back. The center of the curve. I never had this before I got pregnant. Idk if it is related to pregnancy or if it could be me inheriting my grandfather's back problems. I mostly feel it when on my hands and knees. Has anyone else had this? should I mention it to my doctor? it almost makes me feel like my spine is not attached in that specific spot. not from pain from the pressure.