“I don’t want to make a mistake because then I’ll learn it wrong and I’ll never be able to fix it.”
This is just an excuse.
Let yourself learn it wrong. If you’re not open to learning it wrong, you’re probably not open to learning it right, either.
There’s no such thing as a bad habit. Let your habits form as they want to, and pay attention to what happens. You have less control over this than you realize.
The enemy is not “learning it wrong.” The enemy is ignorance.
Besides, have you ever noticed how much you are doing wrong in an attempt to prevent mistakes? That should concern you, if it doesn’t. But, it probably doesn’t, because you are too fixated on the one mistake your teacher got you all worried about.