What Causes Red, Tight And Itchy Scalp And Forehead?

thursday i had a headache most of the day. friday i woke up w/ body aches, headache, fever & chills. i thought i had the flu but no nausea or vomiting. all day saturday i had a fever between 100.8 & 102. this morning i started w/ diarrhea but otherwise feel pretty good. however, something else has me more worried. friday i thought i was getting blisters on my forehead but they never come to the surface. i thought it was from the fever. ever since i have had a red, tight & very sensitive & itchy scalp AND forehead. now i am thinking maybe it wasn't the flu but some kind of scalp infection. what should i do?