Uy, yan na agad dapat malaman ng doctor mo, ha, lalo na kung consistent ang sakit at nag-aalala ka na. It could be so many things, and you really need professional assessment para sure. A few of us mums have had back and lower belly pain din during pregnancy, pero iba-iba ang reasons, sometimes normal, sometimes kailangan ng attention, so please don't wait and just schedule a check-up or go to your OB agad. Alam mo naman, better safe than sorry sa pregnancy, 'di ba? Praying it's nothing serious, sis!