It's fine to be scared. Just don't let it hold you back. And it's okay that you didn't think of it! Trust me, it's very normal. My english teacher just happened to drill those things into my head. *laugh* And really, rereading and rereading it will only do so much. It's better to have someone else read it (a beta *giggle*). And fangirling comments are usually quite appreciated! ^_^ Comment and fangirl freely! I'm very happy that you found a beta; good for you!
*hugs* You're most definately welcome! Keep writing! And good luck!