I am a 31 year old male with possible ALS and I am looking for signs it is something else.
I had a very strange reaction to the EMG/NCV. After no problems during the actual test I developed extreme fatigue throughout my body later the same day. The fatigue is at its worse from 6-72h hours after the test and last up to 3 weeks.

I have had two EMG/NCV studies done. After the first one I found out that I had possible ALS. That night I awoke with massive fatigue which felt like I did not have the strength to breath. I felt if I did not wake my wife to call 911 within seconds I would no longer have the strength to communicate. I then got up to try and put some pants on but I passed out after a couple of steps. At the ER they concluded this was probably a panic attack which I think was what any good doctor would have done. However, I felt that the fatigue triggered the panic not the other way around and my heart rate never increased to over 100bpm. I continued to have general fatigue and weakness breathing on and off for weeks but they severity and frequency of these events was decreasing with time. Also the Dexedrine I take for ADD and narcolepsy seems to help a lot with the breathing. Over the next four weeks I recovered greatly and was able to walk about 6 miles a day at Disneyland over 3 days and easily run a 9 minute mile with only minor leg tightness. Neither of these activities produced any breathing weakness. I still felt maybe I experienced some kind of was a strange kind of panic attack. However, last week I went to the mayo clinic and I had another EMG/NCV test. This time I had my father a M.D. with me so I did not call 911 despite a very similar reaction. 24 hours after the test a pulmonary function test concluded my inspiratory and expiratory force was 30% and 40% of age adjusted normal. Also I have had low grade fevers for 4-5 days starting 24-48 hours after the test. I am hopeful that I will continue to recover from this latest EMG/NCV test and I am likely not to allow them to run another one unless I get much better.

FYI the multiple tests at mayo including the EMG showed that I do not have ALS yet but the doctors think that it will probably progress to ALS.
Also, I have a family history of sero negative autoimmune disease with onset around 30 years old. As you might expect I have no evidence of an autoimmune disease in any of my blood test (including multifocal motor neuropathy). This is not surprising since my other family members that have or had autoimmune disease have ever had positive blood work for autoimmune disease. Has anyone ever had or seen anyone with this reaction to an EMG/NCV? Also, since ALS is diagnosed by the symptoms a patient experiences and not by a causative agent, I think it is likely that ALS may really be many different diseases. It is possible that my EMG/NCV reaction is indicative of a particular manifestation of ALS and my reaction to the EMG/NCV might be useful to understanding how ALS is working.