Bones in back

Lauren • Had my sweet girl 02/22/20 - 5 weeks early due to rare genetic disorder💗 Had my handsome man 09/30/22 - 3 weeks early due to low birth weight💙

I’m 35 weeks. It’s hard to describe but it feels like loose bones in my lower back. They always shift when I walk or roll over. They also loudly pop randomly. Is this normal like my body preparing for labor?