There is no reason to delay washing your hair! You can wash it any time after you start them.
The only times someone would want to delay washing is if they have a very delicate setup like comb coils, which might unravel with washing. However, as it doesn’t sound like you have that startup method, don’t worry.
If you’re really really worried, you can just braid them together in the shower and use a regular hair tie to hold the braid together. However this is probably unnecessary.
It’s normal for your baby locks to loosen up a bit and be fluffy from washing, but they won’t come out.
My only advice is to just avoid getting conditioner on them. Don’t panic if you do, but just try not to condition that bit of hair for at least a month or two, and then only if it feels dry. It’s pretty easy to keep the conditioner off of them in the shower, so don’t worry!
Hope this helps, and I hope you snag yourself a cutie tonight!