Ds had hurt his head when he fell backwards last Friday. Took him to A &E to get it checked out. They were not concerned and were sent home. Only checked by the minor injury unit nurse. Today he has developed a headache. I gave him Calpol. He is not vomiting or feeling sick. He wants to go to bed, mother in law wants me to take him to the hospital emergency just in case something sinister about it. Please advice.