There is very little difference between mistakes and success.
Granted, success is always nicer then a mistake. Makes you feel proud and special and validates all your hard work.
But you need both.
You learn nothing without error, it is the ultimate instructor. And I think I'm okay with that, makes things difficult to regret. Its a strange kind of sweet spot when you loose the fear of mistakes.
Its not a license to throw caution to the wind and run wild naked down the street. (You may regret that mistake later on, think before you head into that one with abandon, 'k?) But its a chance to try new things and toss aside what doesn't work without beating yourself up about it.
Think about it like cooking - you make a recipe and say, "Next time I think I'd do this different." Just like that. Sort of falls in the mistake category but if you noticed, the world kept spinning and you gained inspiration and insight of where you'd like to take the dish next.
That's what I mean when I say there is very little difference between mistakes and success. One leads to another. Can't feel awful about that.
Now that I've spent a solid year working toward the goals that are nearest and dearest to my creative heart, I know what I want I want to leave in the dust and what I want to place on the schedule. I wouldn't have that certainty if I hadn't stumbled a few times along the way.
Don't regret mistakes. Take them for what they are : a stepping stone.