A friend just wrote and asked for writing advice.  He has an editor interested in one of his novels, which adds pressure to his writing.  He said, "My writing scope feels inadequate to the task."  I know the feeling well.  And after I wrote him back, I decided I need to keep my words of advice for myself.  A good reminder when I lose focus.  Maybe you all can be encouraged by them as well:

This is what I suggest.  Feel free to write garbage for the first draft.  Feel free to take risks.  Turn off your mental editor and write from your heart.  Then when you get to the end, read books like Writing the Breakout Novel and apply them to your story.  Bravely slash the stuff that doesn't work.  Add in new twists, deeper conflict, and tangible emotion.  Tie it all together as best you can.  Then hand it over for critique to writers you trust.  Let them slash and suggest.  Take their feedback and use what feels organic to your story.  

Whatever you do, don't lose the passion. And Pray.  Make yourself humble.  Lift it up to God.  Dance for joy because of the opportunities He's granted you.  Revel in the knowledge that God is going to use you in ways you can't possibly imagine.

Then get ready for rejection.  Take it in stride, knowing that it's not a reflection of your worth.  It's simply one step closer to a dream you've allowed yourself to follow.  Being willing to take another step is the mark of true success.