Worry Stone, Worry Story

Today I finally decided my 15-page prologue for What Luck is good enough to send in for the manuscript critique at June's SCBWI conference. I rewrote it for the last time, and read the changes to Ian. He said it's good, but he warned me that if I keep rewriting it, I might kill it.
He's got a point. I'm such a perfectionist, and it can be a problem sometimes. I tend to write something and then keep working at it, over and over, polishing it like a worry stone. Except it's more like a worry story.
I've put aside writing projects in the past, because they weren't turning out as great as I wanted them to be. So I have a lot of great 40 - 60 page beginnings of novels, but nothing really finished, as of yet. But I promised myself that this book will be different - I've got to prove to myself that I actually can finish a book.
I need to keep in mind Anne Lamott's advice in Bird by Bird, her book on writing. She says it's OK to write a "shitty first draft," as long as you keep on writing, page by page. Because you will always revise it later. So I've got to resist the temptation to keep rewriting, and focus more on writing something new that moves the story forward, each time I sit down to write.
Besides, I know that at the conference critique session, I'll get advice and feedback that will give me direction for a productive rewrite - all books go through several drafts before they're ready for publication. But it would be better if I had more of the book finished, so I can apply the feedback to the whole story, rather than just this small, 15-page part of it.
The prologue is done now, and is in the mail, on its way to the conference. No looking back at it - not for awhile. I've got the rest of the story to think about.
So far, I've also written two drafts of half of the first chapter. So now the challenge is to keep on writing, until I've finished chapter one, and then the next chapter, and then the next, page by page, until it's done.
And stop worrying about being perfect.