You never know when baby will make an appearance. It's never too early to prepare. My 2nd was born unexpectedly @ 34+5 perfectly healthy but we didnt even have a car seat to take her home!. just tell him you would rather do it now to avoid stressing later on :)
You are not crazy or wrong. I am on #4 & have typically had everything ready by 34-35 weeks. You never know when baby will come & IF they come early the last thing you will want to be concerned with is setting up a crib.
Im only four weeks and i want to get ready now!
My babies room was ready from about 14 weeks! But i am very impatient! Congrats & enjoy :) xx