Yesterday...

Ever notice how easy it is to beat yourself into the ground about things merely because you can't stop thinking about them? Everyone makes mistakes, so why is it necessary to always think about them. "I wish I'd done things differently," we say.
Get over it!
Yes, I know, I'm guilty, too. But you know what? There's no such thing as a time machine. Sure, it exists in science fiction, but do you really think it's possible to travel back in time? And even if you could, and you tried to convince your past self to do things differently, do you think your past self will listen?
I'm not sure if I would.
Yesterday is dead and over. The mistakes we made might still impact us, even years into the future, but moping about mistakes isn't the right way to take care of them.
Fix them. Fix the mistakes. And if you can't, then live with it. Everybody makes mistakes. It's whether or not you can get up afterwards, brush yourself off, and continue to try that matters the most.
Don't let mistakes win.