My head hurts for the last 3 hours and I have fever should I go to the doctor?

Certainly. There are many different things that can cause this constellation of symptoms, and the fever itself will often contribute to the headache. Some problems that can come to mind are flu, strep throat, viral illnesses or othe rmore severe illnesses. A doctor can help you figure out the cause and treat it, and if your own doctor can't see you that day an urgent care center can help.