Meaning
Closed eyes cast downward, eyebrows drooping and a small frown: a face that has just been let down. It expresses disappointment, regret or the deflated feeling when things do not go your way.
Use it for honest letdowns: “Didn’t get the apartment, someone signed the lease an hour before me 😞” It is a step more openly sad than the pensive face and more resigned than angry. When you are the cause of someone else’s disappointment, an actual apology works better than this face, which can sound like self-pity.