In the old BT there were dozens of stories like yours in the archives. You may be able to retrieve them now that BT is up and running, I don't know.

In a nutshell - your age is definitely in your favor. ALS at that age is almost unheard of. Second, you are going about getting tested, Good! I would bet my house (and I am not a betting person) that you have BFS (or something similar), an annoying, but certainly not a fatal malady.

Terrible weakness is the first sign - falling, etc. My favorite uncle died from it. I am sure that you will be fine. Keep writing.

Mama