Is Occurrence Of Rashes, A Part Of Fever In Children?

My son has had a fever for 5 days, seemed to dubside last night. developed bumps on his face that resemble chicken pox - under his bottom lip on his chin, nose and left cheek. His dr. said he "may develop a rash" after 4 - 5 days of fever....is this the rash he was referring to? He was vaccinated for chicken pox and measels....what should i do?