One of the most debilitating aspects of my ME is that the disease causes me major sleep inversion. On most evenings, after significant enough exertion builds up from the previous day(s), I primarily get a very strong brain wired-but-tired feeling and my gut starts becoming irritated. I also get some worsening of other ME symptoms and, if I do fall asleep, I sometimes get intense psoriasis itching which will wake me up. All of this together is definitely PEM. Without taking some medication to help me fall asleep these symptoms will make me feel wired and awake all night until they start subsiding early in the morning. If I keep adding cumulative exertion and do not aggressively rest these symptoms then become stronger and any sleep medication stops having any effect. My body quickly inverts to sleeping during the day and staying up all night. If I aggressively rest and do as little as possible within a day or two I do not get these symptoms anymore at night. I am constantly having to reset myself, where exertion causes this inversion and then I have to stay up all night and the next day to get so exhausted and try to overcome the symptoms the next evening so I can fall asleep. It doesn't always work and its so frustrating. For me this problem is one of the main reasons why my ME make it so difficult to work and try to live a normal life.