What do you do if you had a dream about someone crying?

The only thing to "do" when one has a disturbing dream is determine how the dream relates to your own life. The person seen crying in the dream is a symbol representing some part of yourself that is hurting. To figure out what part of your life it represents, look for clues in other details of the dream. For example, was the crying person sitting beside a gymnasium, wearing a Basketball uniform? That would suggest that you feel more deeply disappointed about not making the team than you realized. Or was the person standing at the side of the road watching a car drive away? That might reflect frustration at not being able to drive. Each person's dream is specific to the individual, so you must find the clues that are meaningful to you.