My 6 Yr Old Grandson Started With An Upset Stomach

My 6 yr old grandson started with an upset stomach (throwing up) and terrible headache but also complained with his neck hurting. So much pain in his neck that he wouldn't raise or turn his head. He had spent time the day before playing and doing gymnastics. He doesn't take gymnastics, just him being a kid. They took him to the doctor concerned about his neck more that the throwing up. He was sent to the hospital to have him checked for meningitis which was ruled out, I don't know what else they checked for. This is 2 days later and the pain has not gone away (the throwing up stopped after 1st day). It now hurts in his neck, side of his face and ear. When he gets up to play or even walk around very much a very bad headache returns in the top of his head. What Should be done to help him. This is a child that seldom complains about anything.