Let it Flow--On Writing

So, here's my problem:

  When writing my fantasy novel, I usually struggle to find the words when writing. I mean, I really do struggle. It takes me about an hour to write 300 words, most the time my eyes are just scrutinising over word-choices and the flowing of sentences, et cetera.
  I recently wrote a story which explained my entire back story to me, in order for me to drop hints along the way and to ensure I know exactly what is going on for certain characters, and I blasted out a couple of hundred words in a few minutes. Not because I knew what I was doing or where I was going, on the contrary, I needed to plan a lot of what was happening and how it came to affect my current work.
  It was because, no matter what I was doing, I did not care for the words. I knew nobody would ever see this, and that only I, and nobody else would see its content. It did not need to be perfect, like I would like my project to be.

So what I'm trying to get at--I'm trying to convince of this, too-- is that stressing over your work is not going to get you anywhere. It's not going to get me anywhere. That is what a first draft is for, it is OKAY to not be okay.

Thanks, and happy writing!

-Charlie