I would absolutely positively 100% call *her* - if for no other reason that to ensure that you are not charged for the session.

Things come up, however, you are owed an explanation here, and you do not have to wait for it.

You get a say.

Look, I'm all about understanding that this may have been an emergency, whatever, but, this just seems kinda hinky that she couldn't have stuck her head out the door and said "let's reschedule" or something.

I mean, geez.