I feel you so much with that excited feeling and face/neck getting stiff. I also wanna explain everything really fast. The story is just too funny/interesting sometimes lmao.. Makes me happy to see someone else having such similar symptoms. Sometimes I think I have like an actual brain problem that needs medicine to resolve or something. It's my first time actually looking at forums and stuff related to stuttering. I'll try to be more mindful when it comes and take a deep breath/relax myself