Oo, super common yan sa 8 months! A few of us sa friend group namin ay palaging nag-complain ng ganyang hardness, parang brick ang tummy lalo na pagod na pagod, most of the time it's just Braxton Hicks contractions, yung practice contractions ng katawan mo para sa labor. Try mo mag-rest, mag-hydrate well, at mag-relax kahit slight lang; usually nakakatulong talaga yun. But since you're already 8 months, best check with your OB just to be sure everything's okay, lalo na if it's painful or regular na talaga!