Hi there,
Just wanted to try and offer some peace of mind for you. What you described was almost identical to my symptoms. Started off with some calf tightness, moved into both calves twitching non stop for 2 weeks, then had twitching over my body. I was also terrified of ALS. Saw my neuro and he order the EMG. The EMG came back clean and his clinical exam was also clean. He said there is something called begnine fasciculation syndrome (BFS) that can cause the twitching and there is no harm to the nervous system. They don’t really know what causes it, but anxiety and stress sure play a part. I have extreme health anxiety and feel that the months of tension I’ve been having just caused my nerves and muscles to be tense for so long it started the BFS. My neuro said that twitching oftentimes is not the first presenting factor of ALS, and that twitching wouldn’t be widespread. ALS twitching usually starts in on area then slowly spreads and doesn’t stop. ALS is a progressive disease while BFS you can have good days and bad days.
Now, what I’ve done to help my BFS: I’m in therapy to help manage the health anxiety, I’m taking 400 mg of magnesium and a fish oil supplement to help with mood stabilization. I have a family history of fibromaylgia and have a feeling these two issues are related(this hasn’t been confirmed by a doctor yet) and will be getting a second opinion from a renowned neuro clinic nearby. I’m not a doctor and can’t tell you what you have, but hope that my experience can help give you some peace and perspective.