I relate to every thought you voice in this piece.
As a writer who is currently pitching to editors / agents, I feel good when I see a rejection because even that is better than the black hole of no-response-ever.
Many congratulations on your book. Mine was published in 2021, too. And I've personally gone through all those emotions and perhaps, some other dubious ones too. Like, am I even happy? Why do I get this feeling of what-next what-next all the time? Is it bile twisting in my stomach excitement or anxiety? Okay, the book is here. Now, what do I do with it?
Absolutely cluelessness is the constant state of emotion when launching a piece of you in the universe. You don't know the ground on which it landed, where it went, if it made a sound when it landed.
Lovely analogy on the nectarine.