Counter reply and depression. With me?

Is there any problem with me ? Or i am suffering through any disease . Whenever any friends crack a joke on me  or give a sarcastic reply i cannot reply back to them .i cannot think what to reply them and my brain stops working at that moment and i cannot think further .I started getting a bit nervous/scared from that person ,having a feeling that if i talk again they will make fun . I will be normal when a person talks nicely to me like suppose behaviour .I want to get out of this problem and this depression sucks whole day i start thinking about that .Help needed Conclusion: 1) Why the hail i cannot reply back or counter reply them 2) my brains feels like blank at that moment i cannot think . It's feel always scaryness whenever i walk out with  my friends because of the fear that they can make fun of me