Today was a milestone day for the baby in several ways:
1) The umbilical stump fell off. X and J each independently said, "You're not going to keep that and put it in the baby book, are you?" I may have been somewhat obsessively updating the baby book. (I did not keep it, or even take a picture of it.) Kit's navel looks fine and healthy. Yay for our lovely healthy baby.
2) Kit managed to spit up through the nose as I was in the middle of changing a diaper. This was quite alarming for several reasons. First, I thought the sudden sneezing and drippiness was the first sign of a cold, and freaked out at the thought of our 10-day-old baby being ill and having trouble breathing. Second, babies generally breathe through the nose; Kit was very agitated at not being able to do this, and began screaming. Fortunately I had stocked our medicine cabinet with a Nosefrida nasal aspirator, and I kept a handle on myself long enough to direct X to grab it for me so I could suck out the milk-snot. J called the pediatrician, who said to clear out the nose with a couple of drops of saline solution and more aspiration, so we did that--I'd also stocked the medicine cabinet with saline and told X exactly where it was--and once it became clear that the nose wasn't runny and it was just a onetime thing, I handed the baby to someone and went off to sob.
I am very embarrassed that I reacted that way. I'm generally calm in a crisis. I keep reminding myself that I did all the right things and that I was able to identify the tools to use and tell people where to find them and make use of them. I didn't let the panic get in the way of responding quickly and correctly. And I know it's normal for new parents to be easily agitated about anything that might be the slightest bit wrong with the baby, especially when we're underfed/underslept. But still, I panicked, and I don't like that I panicked.
3) Kit drank four ounces of milk in one go. Turns out this is way too much for a ten-day-old baby. To my surprise, it all stayed down, but I spent about an hour doing tummy rubs and bicycle legs and diaper changes while Kit flailed around and strained and looked very uncomfortable. Poor wee thing. I finally induced sleep with a lightly swaddling sleep sack--it's warm enough in here that Kit was just wearing a shirt and a diaper, but apparently the baby has already formed the impression that that is daytime clothing and nighttime requires pajamas--and a bit of pacifier-sucking. (Apparently bedtime pacifier use significantly reduces SIDS risk, including for low-risk babies. I'd been avoiding it because weaning babies off of a pacifier can be very difficult, but I shall avoid it no more. Kit has literally zero identifiable risk factors for SIDS, which is a very reassuring thing to know, but why take chances?)
Lesson learned: if Kit chugs three ounces and claims to want more, give a pacifier instead and wait for digestion to happen. Everyone will be happier.