In 8th grade, my math teacher had a poster in the room that said something like, "It's not a mistake until you refuse to correct it."
Given that she was a math teacher who marked you wrong when you gave a mistaken answer on a test, the poster kind of struck me as odd. Obviously, you can make mistakes! But, I think the general message of what the poster was conveying is true; that is, it's okay to make a mistake.
Here's the thing: whether it's writing, a test, a chore, or even a video game, you are going to make mistakes, and that's a good thing. The only way to make a mistake is to do something, so if you're not making mistakes, you're probably not doing much!
And sometimes, you're going to make a huge mistake like forgetting to save an essay while you're writing it (and then have the power go out right when you're finishing up), not studying for a major exam, or not checking the expiration date on a can of soup that's been sitting in your cupboard for months. Occasionally, these mistakes will haunt you for some time like when you're wrong about a friend, or when you royally screw up something big (or when you're in the hospital for a few days for food poisoning...).
Huge mistakes happen to all of us; everyone you know has royally screwed up at least once in their life. You might even be cut from a team, suspended from school, or fired from a job because of what you did. But this is how you gain experience and how you learn. A mistake is an opportunity to do better and to improve. When I was in law school, a professor told me once that he much rather a student give the wrong answer when he called upon them because that gave him an opportunity to actually teach.
In regards to writing, you're going to mess up and that's okay. Listen to what your reviewers are telling you, and then think about how you can improve. Likewise, don't be harsh on someone when they make a mistake. Eventually, you're going to be in their position, and when you are, you'll appreciate it when the person pointing out your error is respectful and kind about it.
The first video is one I send to new and worried writers regularly, and the second one is just excellent life advice that Rowling gave at the Harvard Commencement.
