DD bumped her head - fell over as the train jolted, whacked her head on the partition wall, with my five year old on top of her. Was awful. She cried a lot at the time, but now seems fine, got a slight lump (is on the 'thick' part of her head, to the side, about an inch or two above her ear. Eaten her dinner, doesn't seem bothered (unlike me!). I know the drowsiness is the thing to look out for, but are there any other indicators of problems that I should look out for?