What does it mean for a blind date to send me an expression pack to shut up?

The blind date sends you a "shut up" expression pack, which is usually a light and humorous response.

This means that he is surprised, funny or joking about the information or words you sent. This expression pack may be an exaggerated or funny expression, which is used to convey a joking, laughing or joyful mood. It is an interesting response to your own words or a situation.

It's best to ask the other person's intention directly to make sure that he understands it correctly. Treat this emoticon with a relaxed and open mind, and actively communicate with each other to avoid misunderstanding and confusion.