As suzeeq says, knowing how to fix dropped stitches with a crochet hook really helps. It really does make the anxiety go away.
Heck, I dropped a stitch on the sock I'm working on now at one point, and didn't notice until it had unravelled down 4 rounds. One crotchet hook and 5 seconds later and everything was fine.
The more practice you get, the more you'll realize that not all mistakes are permanent, and almost none of them require frogging the whole work and starting over.