Uy, totally normal yan, lalo na first time mom ka pa lang! Ang balakang mo ay umuunat talaga dahil sa hormones at ang bigat ng baby, kaya yung ligaments mo nag-relax na para maghanda sa labor, a few of us moms actually experienced the same thing, parang pulling sensation siya around the groin area, sobrang uncomfortable minsan. Best thing is to rest, use warm compress, at matry matry mo stretching exercises pero gentle lang, pero if it gets really painful or may other symptoms, mas better tawagan mo doc para ma-check lang to make sure lahat okay, okay lang maging paranoid especially first time!