This obsession is taking over my life. I don't know why I'm so scared of this but I'm terrified that I have this condition. It's on my mind 24/7 and now I'm scared to leave my house.

Often times when I'm exercising I get really tired afterwards. Like if I go for a run immediately afterwards I feel so sleepy that I need to lay down for about 30 minutes until I feel better.

A few weeks ago I wanted to prove to myself that my obsession is false so I decided to go on a long walk (2.5 miles one way). I felt good once I started but once I got to the destination I felt extremely sleepy. I can go to the gym and lift weights and not feel too bad afterwards sometimes.

I feel so alone because I can't find anything on the internet of anyone sharing this obsession. I feel like I truly have cfs and my life is over. I have recently got a full checkup and the doc says I'm healthy. 

I don't know if I'm imagining this or what. I'm too scared to exercise now in fear that it will make me sleepy. Does anyone share this fear? Can i worry this fatigue into existence? I'm so scared