When you hear something that
A) turns you good mood bad, such as the mentioning of an ex, or
B) turns your bad mood good, such as the mentioning of an upcoming event.
Joe totally had a face flip when you mentioned Jen tday at the water cooler.
When your face in a mirror or selfie looks drastically better in reality. People who look bad in selfies but good in real life do not have this condition.
“I thought he was hot, but it was a bad case of flip-face. Not cute in person at all”
“I learned I had flip-face when I turned off front camera mirroring. Now I don’t even recognize myself.”