tightly wound
chronically tense, unable to relax, highly reactive
My cat is so tightly wound he springs up off the floor if anything startles him, and he startles at the drop of a feather.
tightly wound
Angela Martin from the Office
Dwight: "She's not the kind of person you would expect to see on Valentine's Day... She is like..."
Pam: "like tightly wound?'
Pam: "like tightly wound?'
Tightly wound
Rachel.
Rachel is apparently tightly wound