I am afraid of retarded people

Hi, I am a 16 year old boy who is terrible afraid of retarded people. I don't know how or when it started but it's crazy. Like today, I saw a retarded boy with my aunt and I was about to go crazy. I know it's mean but I was about 2 swing on him kuz when i see somebody like that, my body locks down, I can't move and I feel like I just saw a ghost.