You are much stronger than you think.

Most people rate their own strength using the worst ten minutes of the month, and not the eleven hours either side of them where they functioned perfectly well.

You'd never assess a bridge by how it feels in a gale. You'd look at what it is still doing the following morning.

The self-estimate gets taken at the low point because that's the moment that feels most honest. It isn't. It's the most vivid, which is a different property altogether, and a far less reliable one.