I agree completely with mrsD about keeping a journal. You have been treated by many different docs for your MG - which puts even more responsibility on you to keep great records.

Re: your strength....perhaps you hadn't worked out for a few a days prior (because you had been feeling so weak) to your strong days. I encourage you to keep a schedule of you workouts versus your strong/weak days. I'm not suggesting you eliminate work outs...but rather, learn how to best integrate them into your life to try to help limit MG peaks and valleys.

Yes, and you can be creative too.

Different ink color for different strength states. So at a glance you can see strong days, moderate days, weak days.
A small calendar included could have the color put in on those dates, as well. Doing creative things, can make it more fun and less of a homework type chore.