My son, who is two, has bumped his head pretty good several times already. (Typical BOY!) Anyways... the first time was in the bathroom on the ceramic tile floor. He tried to take off while I was trying to dry him off after a bath. I was pretty freaked. Ceramic tile is pretty hard.
Here's the advice I got... If he can walk and talk as normal, his balance is normal, his eyes look ok, no vomiting, and no loss of consciouness, he's probably fine. they said to just keep a watch for the next 24 hours.
If you called the doc or a nurse line, I am sure they asked all the right questions.
With three pretty nasty bumps on the head, my son is still very bright for his age, so I don't think there was really any damage. Just a few giant sized bumps with some nasty purple coloring. (And one was right before his 2 year old pics! Eeek!)
So if her behavior seems the same, no vomiting, and you have a bump (rather than a dent) I think you are fine.