Here's another account of one of these phones bursting into flames while NOT Charging. If you're still using one of these phones do yourself a favor and do an the manufacturer and government requested and turn it off at the very least if not outright return it.
Do you really want this thing in your hands, pocket, of on your face burst into flames? It might not happen to you but these recent incidents those people thought the same thing and it happened to them.
Sure it's a bit of downtime without a Note but it beats the worst case scenario.