I guess I'm lucky in a way. I have never been especially athletic or well coordinated, so shooting like Robin Hood has never been in the cards. So a bad day is not such a crushing blow to me. When it all goes to hell on a toboggan, I just put the bow down thinking things will be better tomorrow, and they usually are.
Archery, like life, is cyclical - some days you are up, some days you are down. This happens to all of us, and if you think about it, it happens on the job a lot as well. Yet, after a bad day, we all get up the next morning and go to work confident that we are good at what we do.
This is our recreation and should prevent ulcers, not cause them. We do this for fun. Besides, no matter how shaken you are, your dog still thinks you are a hell of a fine fellow, and he's probably right. Be serious but too much so.
In the final analysis, confidence comes from skill, and that skill comes over time and is a function of repeated good form. Hang in there, the consistency and it's resultant confidence will come.
O.K. Sam is off the soap box.