I noticed that my eyelid was drooping, but thought I had just rubbed it too hard that evening; when it did the same thing the next night, I thought I might oughta have it looked at.
At the time, I didn't think anything of it; when the icepack test at the neuro-opthamologist's office was positive, I started looking into what the symptoms of MG were, and realized all of the stuff that I had been attributing to getting older/being out of shape/being fat and lazy/etc. were all early indications that I had MG.
In a way, it was a relief to know that all of the stuff that had been happening over such a long period of time actually had a "reason"; it also gave me permission to quit pushing myself (to increasingly unobtainable limits) and to take it easy instead.
I will have to say, though, that pain hasn't been an issue for me at any point along the way; it may be that the Lupus makes things worse. If you have Sjogrens, a gluten-free diet might go a long way towards making those symptoms less of an issue; many people find that it helps.
Hope you find some answers soon