duck and hide

I cleaned my Curly's snake tank, and changed the type of subtrate (repti-bark->newspaper) and cleaned one of the hides, it was the one he ALWAYS went to, his favorite hide. After i put him back into the cage, he totally ignored the old favorite hide and won't go into it. Now he goes into the corner of the tank and balls up against one of the other hides. There are two hides on the cool side, but he won't go into them, and i am absolutely sure he can fit iinto one of them, cause like it used to be his favorite hide.
That's wierd. What do you all think?

uhhhh....maybe he grew

I wouldn't sweat it too hard. Hissy used to do that from time to time. He may just be mildly freaked out by the new substrate. Give it some time, he will be just fine.