How do you know?

Ok so, I’ve noticed my belly gets really hard every now & then. It’s not always an uncomfortable feeling but I just know when it’s hard. Does that mean it’s always Braxton Hicks? I thought our bellies get hard because of baby’s position (his back is facing front) lol

You guys also say it’ll feel like a tightening experience in your belly, I don’t always get that feeling but my belly will be hard as a rock lol