Nah, it's not too early! We don't put up that much stuff, but our window lights went up on Thursday and the tree is going up tonight. I usually do it over a week or so, never seem to have enough time to put everything up all at once.
DS and the puppy will no doubt dismantle the tree repeatedly and we'll get sick of putting it back together again but DD is desperate to get everything up. Once the advent calendar is on the go, Christmas has arrived, as far as DD is concerned.