What Causes Headaches Followed By Cold And Cough?

My 13 year old has been complaining of headaches, a light headed and off balance, can barely walk or weakness, sniffles, runny nose, coughing, or cold like symptoms, states he thinks he blanked out yesterday or just dozed off also this morning upon waking he asked if he ran into something or hit his head on something because that s what it feels like. Can you tell me what is the problem? What should I do?