1. The 'I am a flipping genius' stage
This is the point where the story is flowing strong through your fingertips, the narrative feels good, and the characters are chattering non-stop. You don't feel like you're even working - you're just the conduit through which the words come. You are riding high, you are sailing, you're living the dream, you're creating a masterpiece, you are a flipping genius.
You're not, but you'll learn that soon enough. Enjoy this stage because it won't last for long.
2. The 'Maybe that sequence wasn't quite as perfect as it could be'
Most likely, it isn't. If you learn anything as a writer, it's probably these two things: A: That there is any number of ways to write a particular sentence, paragraph, chapter, book, etc and B: you'll always think of a better way to do it after you've sent it to your friend/mother/critique partner/editor/planet-at-large. If your trusted editor/friend/critique partner tells you it's fine, let it go or you'll be stuck in the land of Never-Ending-Rewrites.
3. The 'Wait, how did I miss that?!?' stage.
Little Joey was in the living room with a red shirt and a rubber ball. Next sentence he's miraculous changed into a blue shirt while still playing with his baseball. Little Joey, it seems, is a magician and you, you realize, have a major re-write on your hands as a result.
4. The 'I'm done - throw it all away' stage
Giving the matter careful consideration (read: being in the midst of an emotional breakdown), you decide that you stink, your words stink, your story is stupid, your characters are cardboard, and your plotting has more holes than Swiss cheese. "I'm done," you declare. "I'm through. I'm selling my computer and taking up tennis!"
Only... you aren't. This is only stage four of the Circle and what's important right now is that you THROW NOTHING AWAY. Trust me. Don't. You are in no fit stage right now to know what is good and what is not and if you aren't careful, you'll chuck months of work that only needed a fresh set of eyes to tell you that it's all right if Sally and Biddy are distant cousins, because Aunt Judy made a will that only favored Sally anyway.
The trick to surviving stage 4 is to walk away from the computer and do something else. Get away, get some perspective, and only come back when you reached...
5. The "Oh, wait a minute - what if I just..."
So, you're outside, mowing the lawn and listening to Adele wailing on and on about her broken heart when suddenly, it hits you: your story isn't broken. All it needs is a quick fix on page 52! If you put Joey in the kitchen with a yellow shirt and a basketball, all the sudden everything makes sense and you don't even have to mention how Sally and Biddy are related! It all works!
At this point in the circle, you rush back inside to pound on your keyboard, all the while whispering to yourself, See? You are a genius!
And thus the great cycle begins again.
There are going to be days when you'll be begging to get off this crazy ride, but you probably won't. There are reasons why we all love carousels and Ferris wheels - I guess there is something addictive about the highs, lows, and whirl-abouts, and that feeling of accomplishment you get when you look back on a project and think, "Well, for better or worse, I made that." My advice? Sit back and enjoy the ride - life doesn't get better.