I'm nervous about moving on in the job world so I'm comfortable where I am.
What happens if something goes wrong with your job though?
I'm doing everything I can to make my job work out and not let everything crash and burn.
While having job-related fears is normal, you shouldn't let your fears hold you back from doing what you should with your job. If you aren't reaching your full potential, you ought to work on being more bold and going after opportunities instead of being scared that they won't work out.
It's okay I can take a step back and not try at my job if I want.
I think that you should not step back! You should keep working hard if you want to remain in a nice comfortable job like this.