He is just teasing you to make you flustered, upset and embarrassed. He does it because he knows it upsets you and he thinks it is funny. Next time he does it , don't let him see that he has upset you. Calmly tell him that the same way he feels when you trade him about having a crush is the same way he is making you feel. Tell him you are sorry for doing it to him in the past and you understand he does not like it so you will respect him and stop doing it to him. Tell him you would like him to respect you as well and not tease you because you do not like it. It is important top treat others how you want to be treated. If he continues to do it, Don't give him a reaction. Ignore him and act as if he is not there until he stops. :)
