You didn’t build your confidence in a weekend and you won’t lose it in one. That goes both ways.

Confidence is an accumulation, not a mood. It got built out of hundreds of small pieces of evidence that you can do things, and one bad afternoon cannot delete that record, though it is extremely good at making you feel it has. The same logic runs the other way, which is why a single great weekend never quite sticks.

After a bad day, go to the record instead of the feeling. Things you have done before that were hard, times you were sure it was over and it was not. Then do one ordinary competent thing to add to the pile.