I'll admit I'm biased up front, we left our 9 week old puppy overnight, and he was dreadfully behaved for a week after.
I'd be inclined to reschedule the holiday, as she's still very young, but it's obviously up to you - I felt that had we left our boy for longer he'd have been even worse, and we left him with his dog mad granny, and he still reacted badly.
Saying that, you know your own pet best, and I'm sure she'll do fine if you think so. I'm also not an experienced dog owner, so probably don't know what I'm talking about, just wanted to give you the benefit of my limited experience, although negative.
Shona