Tightness

I’m about to be 23 weeks in a few days and lately when I get stressed or my adrenaline is up or even just walking around/sitting up for awhile my stomach gets so tight and uncomfortable. Like the only thing that helps is when I lay down and truly relax my body and then it finally softens up a little. But seriously everytime I am stressed or sitting up it gets so tight. Is this normal?? Or has anyone else experienced this??? I heard it’s Braxton hicks but why would that be happening over stress or adrenaline?