It is Christmas eve when scrooge gets home.its 2:00 a.m. when he goes to bed. Why is he confused when he wakes up?

Scrooge meets Marley's ghost when he gets home, who warns him about the three spirits who will come to meet him. So it is past two when Marley and Scrooge finish talking and he finally gets to bed. When he wakes up it is still dark and the neighbouring church clock is striking twelve. At first, he thinks that the clock must be wrong, and checks his repeater(which is a kind of a clock or a watch). But that too shows twelve. He is pretty sure that he went to bed and two, and couldn't have slept through a whole day. He also feels that it couldn't be that something happened to the sun and it was noon. This is why he gets confused.