you're doing 3 things wrong:
1. flying without an instructor
2. flying a cub as a first airplane
3. assuming the sim is the same as the real deal
as everyone has said go to the local field, seek help. You'll find great folks there, that'll jump at the chance to help you
this is a great hobby full of personal rewards if entered into correctly. Or can be the most discouraging thing in the world
Good Luck