My son fell at school this morning and landed on his back. The nurse gave him a bag of ice and sent him back to class. When I picked him up and he sat down in the car he started crying because it hurt again. I checked it when we got home and saw a bruise wit red speckles on his lower spine (halfway between his hips and ribs). I gave him some children s Advil and held an ice pack in place with an ace bandage . It is still tender, but he is able to walk and stand fine. The pain is worse when he bends to sit and of course when he leans back when he sits down and puts pressure on it. Are there any symptom I should keep an eye out for that would suggest I take him in to the hospital tonight?