I thought it didn't let her back inside because SHE DIDN'T HAVE A KEY and the door was locked. No one gets in without a key, except maybe the Doctor (oh snap).
Sure, but writers don't just throw random dialogue in for no reason. Clara could have easily said, "It's locked!" instead of "I don't think it likes me."
Given the little that we know about Clara, it's quite possible that she is some kind of temporal paradox. The TARDIS hates those.