I'm not asking anyone diagnose anything via the Internet, and I know that just because one person has a particular thing happen doesn't mean it will apply to everyone in the same scenario - but having a mini panic and hoping for a little bit of reassurance.
DD (9) has shingles. Apparently this is pretty uncommon in healthy kids (unless maybe you had chicken pox under the age of 1 - she didn't, she was 5). It's more common if you have some kind of immune issues...which has sent DH, who has form for gravitating to the worst case scenario whenever anyone has a sniffle, off panicking about cancer and leukaemia and survival rates for every kind of terrible illness you can imagine. He's actually medical (although works in an area where he sees the worst case of everything, so I think it skews his view) so it's hard to stay calm when he's imagining all the terrible things it might turn out to be!
Perfectly healthy kids sometimes get shingles, right? It's not so vanishingly rare that it's likely a sign of some sinister underlying condition - right?! Anyone's kid had it without anything else going on?