Thank you so much for the prompt reply.
If it's lasted that long, it isn't a herpes cold sore, and it doesn't sound like one anyway. I don't know what it is, but it sounds like something that can be left alone. If it stays for a month or more, have a doctor take a look. Sometimes kids get superficial blood vessel collections on the face that look red. They can be cauterized, but only if having them is bothersome. Nothing serious in any case, so there's time to look into it.
Best.
Dr. Rockoff