I’m 15 and have a red pin prick, non blanching

Patient: I’m 15 and have a red pin prick, non blanching rash on my chest and left arm. I have been feeling tired and achy for the past few days and have vomited once. I’m worried it may be something bacterial/viral however my parents are very difficult when it comes to illness. Can you help me figure out what I may have?

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I'm 15 and have a red pin p...-1

Doctor: