Summary: The Doctor isnât prepared for an unexpected visitor.
It’s not possible, the TARDIS is in flight, it simply can’t happen! The Doctor’s so shocked that all he can say is “What?” and “But…” and “You can’t do that!”
The woman in the white dress doesn’t seem to be having the same problem with words, ranting about him kidnapping her, which he didn’t, he’s sure of that, and demanding to be taken back immediately. Which he’d be happy to do, because a loud redhead appearing unexpectedly in the TARDIS is the last thing he wanted, even if he didn’t know that until it happened.