Do I have a cold? Symptoms of a cold?

Today at school I had a terrible headache and was super exhausted, I felt light headed and just awful. When I ate lunch I felt a little better, but towards 6th period and now at home I feel worse. I don't have the sniffles, just feel REALLY tired and headache. I know that the flu is going around at my school, one of my classmates left early because she was sick. I don't have any appetite either. Do I have a cold? Advice?