Ay oo, ganyan talaga kaya sa pregnancy lalo na pag malapit na! A few of us pregnant moms namin nag-usap about this, and parang normal lang siya kasi ang gas at bloating ay super common sa third trimester, ang baby na kasi ay pushing sa lahat ng organs mo so awkward ang digestion. But since 31 weeks ka na at masakit talaga, better check with your OB lang para sure, especially if may iba pang symptoms like constipation o change sa movements. Drink lots of water and try small frequent meals muna, it might help!