I've only started pursuing a diagnosis for the past ten years but a friend reminded me recently of a time, about twenty years ago when I worked as a house cleaner. The job was more labor intensive than I was used to and I was exposed to a lot of chemicals. After work when my friend would talk to me, my head would fall forward, and I'd fall asleep. There were times that I'd even fall asleep while eating dinner. I was so exhausted and looking back on it now, I think not only the use of muscles was my problem, but the exposure to chemicals. I was only able to work at this job for about a month.