Mirrors don't freak her out. At least, not initially. But combined with the claustrophobia she hadn't even really realized would freak her out, it's definitely enough to get a little wiggy! And she'll begin to wonder if she's not the only one here. Girl's got some serious paranoia... and, after all, this is a magical island. She's pretty sure nothing is impossible here.

So yeah. Seeing double, triple, quadruple? That's gonna freak her out. Just a little. (A lot.)

As for your question about struggling with isolation... Oh yeah. If there's one thing that absolutely terrifies her, it's the thought of isolation. And she begins to wonder if she's going to die down here, all alone. Nothing is scarier than that. And, if she's cold and tired... that definitely makes all of this feel a thousand times more intense.