"After that, she promised me she would do a good job."
I'd say: ...she promised me she wouldn't do that again.
"But sometines I'm stressed out; it keeps me thinking."
I'd say: But, sometimes, I feel stressed.
"I continually doubt if she's doing a good job and nag her."
I think you meant: I continually doubt if she's doing a good job, so I nag her.
"I think I'm born that way".
I'd say: I think born this way.
_
I hope it helped, Mari <3