Headaches are often a sign of dehydration. When somebody stays out in the sun too long and starts getting dehydrated their head will start pounding because their is not enough water to keep you from thinking about being cooled down. So the answer would be dehydration. Hope this helps! Have a nice day!
Most liekly ice because ice can cause burns onto the skin which are pretty hazdous just like they make creams to cure cancer and they burn holes into the skin
