When you are Rick Roll'd so many times in a row that you begin suffering from symptoms of annoyance, complete frustration, redness of the face, and the urge to post offensive comments.
You: OMFG I swear if I hear "Never gonna give you up, never gonna let you down.." I will kill somone, and let's hope to god it's Rick Astley.
Friend: Dude we need to get you to a doctor, you may be suffering from Rick Rollitus
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"