Even if you go into a book knowing your plot and your plot never changes from your plan, you still don’t know what you’re getting into.
Making messes isn’t just okay, it’s necessary.
For most of the process, nothing but faith, fueled by your own stubbornness, will be pulling you along. The work that you’ve done on the book so far won’t be much comfort, because so much of it will be insufferable crap, until the very last moment, when you figure out how to fix it and everything comes together.
Everything will come together, as long as you don’t lose hold of what the soul of your book is, work as hard as you can, and don’t give up.
When it does come together — that moment is the best feeling there is.
The next part, where the book stops being just yours and becomes other people’s, will be thrilling to your spirit, but there are aspects of it that will possibly be too strange and surreal for your quotidian little soul to process. You may be overwhelmed, scared, or hurt on occasion. That’s okay; you’ll get your solid footing back. Just let it happen, observe, try to grow, and be grateful.
And in the meantime, ground yourself with a new project.