Hi Shannon,
Jaw fatigue was one of my early symptoms for MG with mouth muscle problems, i.e. difficulties to put my lips on a glass to drink… then everything went rapidly out of control due to the prescription of a medication totally uncompatible with MG and the dx became evident 2 weeks later: bi-lateral ptosis, double vision, swallowing difficulties, blood work and EMG…
I hope your dx will be quickly clarified, one way or the other, so that the proper treatment could be installed.
Maurice.