Hello, I Just Came Home From The Emergency Room. My

Hello, i just came home from the emergency room. my 4 year old son closed his mouth very hard while eating a lollipop. he was in so much pain on the upper roof of his mouth toward the back. the er nurse and doctor said it's just bruised and no need to worry. we are home now and he is so uncomfortable and in pain and complaining - in and out of sleep and waking up because of head pain. i called back the er nurse and she said it could be because the mouth pain is radiating to the head. and no need to worry. have you ever heard of this injury and do you have any advise or feedback?