Mistakes are something to learn from. Of course they make you feel bad, but the fear of making mistakes can't stop you from moving forward. Only if you make mistakes you'll know best in the future, you'll know what to do and what not to do.
If we didn't make mistakes, we would never learn.
In addition, it's something that happens to all of us. There's no person in the world who hasn't made mistakes.
We can do two things:
We can regret them all our life and spend it feeling bad with ourselves because we made mistakes, or we can learn from them and become a better person. What do you prefer?