It all sounds familiar to me, especially the clapping. Sometimes on a day when I don't feel weak, I notice I can't clap for long. It's quite common for people to test negative for MG at one time, and positive later--or to continue testing negative and still be diagnosed with MG. You need a test called a single-fiber EMG (SFEMG). Not every neurologist can do this test--you'll need one who specializes in neuromuscular diseases.

My MG took 15 months to diagnose because I don't have eye symptoms. At the time, my only symptom was a weird, swaying walk.

Abby