A friend of mine, years ago gave me the best writing advice I could have ever asked for, and I didn't even have to! She said, "Don't worry about what you have written, making it perfect and editing it now as you go. Just write," and she couldn't have been more right!
Sitting and agonizing over your story as you writ will only stop the writing process. Seeing it a second time, going over it and really reading it as a story instead of pieces and scenes helps tremendously in doing full bodied edits to you story.
So when writing, don't worry about writing a sentence you don't care for or a feeling that you might need to suss out a character a bit more. Stick to your outline and story and write because after all, your first draft doesn't have to be perfect, it just has to be written.
I'll be back later this weekend with another blog about San Diego Comic Con and new TV, movies and more coming up soon. Ended up being a comic can't this year so keeping my eye out for all the exciting news coming out of the convention!