Re: How long before you dry up? Plugged ducts....
The only reason what you're experiencing might impact you with your next baby is if you end up with a breast infection due to plugged ducts turning mastitis and then an abscess. It's a very unlikely outcome, but I still think it makes sense to take out a little milk right now (preferably by hand, but by pump if necessary). Take out just enough to restore comfort, and you won't risk increasing your supply. Your milk will still dwindle away.
So, is this normal? Well, it depends on what you think "normal" is. Biologically speaking, what is normal is for weaning to occur very slowly, reducing the likelihood of engorgement. Either mom would become pregnant and her supply would diminish or vanish, or the baby would eventually outgrow the need to nurse and gradually self-wean. It sounds like you weaned a bit faster than what is biologically normal, YKWIM? After all, you baby isn't yet quite a year old, and until around the first birthday (and sometimes longer) a baby's primary source of nutrition is her mother's milk. So your supply as of a week ago was probably a lot more abundant than that of someone who was weaning an older toddler.
When you ask "will me drying up clear the way for the next baby in a few years" are you asking about fertility? Or are you asking about breast function?
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
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