Sounds like a Herpres type #2 cold sore. The bump and discoloration are similar to my break outs. It's a common virus if this is the Herpes virus that causes cold cores not genital herpes.
You might have acquired it from a friend or someone else tokin' on your piece.

Or, get it checked out by a doctor because I may be outrageously and dangerously wrong.

Best of luck

Dave :stoned: