Attempted Teeth-Grindin in Sleep?

Jus now while i dozed off in a short nap, i felt my teeth clutching very tightly... to the extend i can feel it.. as in i know... even in my sleep, i can feel the force of it lor.. very weird & kinda worryin... Am i attempting to grind my teeth or wat? Why like dat huh? Too stressed or wat? *puzzled*