Mama, please see your OB as soon as you can, ha, belly pain in pregnancy dapat i-check talaga, lalo na kung may hardening. Better to be safe! At 5 months, some stretching and tightening is normal, pero kung ang sakit ay persistent or sobrang intense, dapat talagang may medical clearance. A few of us moms experienced cramping and Braxton-Hicks contractions during that stage, pero yan kailangan i-confirm ng doctor, hindi lang assumption. Don't worry too much, marami kaming kaibigan na nabigyan ng proper guidance lang ng OB at naging okay naman, pero kailangan talaga ng check-up, sis. Keep safe!