Uy mama, please visit your OB or midwife right away para ma-check properly, belly pain in pregnancy ay kailangan talagang i-assess ng doctor, especially to make sure everything's okay with baby. There are so many reasons it could happen (ligament stretching, baby movements, digestion issues), pero yan ang job ng doctor to rule out anything na kailangan ng attention, don't wait on this one, ha? Tingnan mo kung may clinic or barangay health center malapit sa inyo, or if it gets worse or you see spotting, go to ER na agad. Take care, mamsh!