my niece is 16 month old, she sat on the edge of her toy car and fell backwards hitting the back of her head on the edge of the wall, she was probably a 1 foot to 1 foot and a half from the wall, she immediately cried a lot for about a minute or so, she has a bump, no too big on the back of the head, it is long, this is why I am sure she hit the edge of the wall. After her fall she seems ok, playing, laughing and acting normal, should we be worried and rush her to an ER?