The way I work, I have a strong idea of how the story begins, a sortakinda idea of how it ends, and some probable things that will be somewhere in between. None of this may survive to the final draft (exactly where the story begins may shift back and forth in time. In first draft I may start too early or too late; the ending may be similar to, but not exactly, what I thought it would be, and the events in the middle may change sequence, with some dropping out.) So this current draft, still quite messy (messier in some places than others), is "normal." Normal for me. Not for every writer.
First to main drafts are often partly fun--the story is galloping ahead strongly, full of its own energy--and partly maddening, frustrating, and downright difficult. Again, that's my experience. When a story hits a bad patch and bogs down, I have to figure out why (did I go charging into a blind alley? Did I misunderstand a character's motivation? Something else?) and then figure out how to fix it. The techniques for fixing first-to-main draft problems are somewhat different from those needed for revision, where the story itself is fixed, but needs work to make it better.
This particular book has uneven energy levels; the story is much "slower" in some places than others. Some of those things will have to wait for revision, when the story itself is set (or I hope it's set) because the energy needs to feel more intense in some places and exactly where will depend on the whole story being out there for me to see as one piece. "Where" is not only a matter of what percent of the book, front to back, but "where" in terms of depth: which layer of the story(and how many layers) is carrying the energy. The energy of motivation shifts within characters, and between characters: A may be acting out of a different level of motivation than B, not merely in opposition to B. But other places may need an "energy boost" even before revision, if I've failed to show a character's complexity early enough.
For me, a good main draft, growing out of the first awkward lunges into the story, puts more in than it needs--more of everything--as if making the block of marble from which the statue will eventually freed, as revision "just cuts away everything that doesn't belong." So it needs bulk, made of everything that occurs to me while working on it: incidents, thoughts, motives, characters, arguments, long later-defined-as-boring sections of musing by this character or that, descriptions, straight narration, the dreaded (by rule-makers) "as you know, Bob" explanations, backstory for everyone...all piled up into a vast file (these days), supported by another file of notes from research (and the books that accumulate on or on the floor by my desk, so I trip over them sometimes when I get up), files of names that appeared and were used in the book, and so on. And on.
And still it never quite has everything, so there's first-drafting inserted into the second main draft, to be shaped and chiseled and sanded into place, and then a complete front to back for the third main-draft, and additional partial drafts, and...one day suddenly the thing is done, for good or ill. It's sick of me; I'm sick of it. It gets another run through the spell checker and another fast read and check that the header is OK and there's not a hidden [needanameforthisguy] note to myself somewhere in the middle. And it's off to Editor, who will find things to say that require more revision. But in the meantime I will take three days off of that book, one day at least completely off, on which I should (but don't always) get all the research sources for the book off the floor (at least) and off my desk. Then start the next. Sometimes with a couple of hours of actual first-drafting, sometimes with a walk outside to let whoever is carrying most of the story in the next book talk to me.
I'm not there yet, with this one. But getting the first/main draft down, enough bits of this and that compressed into something large enough to hold the story I want to carve out of it, is the longest part of the process. And I am almost to that. Best get back to it.