There I responsibilities that need fulfilling sending shots of dread through my chest whenever I think of them. They’re on the calendar or they have an approaching deadline. They feel important. I probably volunteered for them. Still, I can’t get feel anything but impending doom when I think about them, and my mind produces scene after scene of disaster, mostly revolving around the certainty that I won’t be prepared and people are disappointed.
Do you do this?
The only thing I’ve found that relieves this dread is the performance of the responsibility. Take Christmas Eve. My responsibilities for that are clearly defined, and I know them weeks and weeks out. Still, as the day approaches my breathing gets short and my sleep is visited by dreams in which I show up to the wrong church or without my shoes. And this is after 17 years of doing it. Yet in every one of those years, the moment arrives when I have to open my mouth and start speaking, everything slows down and the breathing deepens. It always goes (more or less) well. So why does my brain spend endless days certain that it won’t?
YoRocko! 
I totally understand. Even the tasks that I thoroughly enjoy often bring a sense of dread, for like you, I worry about letting people down, not meeting expectations.