When have you felt uncomfortable around a student with a certain disability?

"A few years ago, I was left alone in a classroom with a student with some aggressive tendencies. It was only supposed to be for a few minutes, but that turned into thirty minutes. The student knew lunch was approaching, and he began exhibiting some behaviors that I knew were beginning stages of him truly acting out. I did what I could to distract him and engage him in something he enjoyed, but when I started to feel uncomfortable, I called the main office for back up. As soon as another adult entered the room, I immediately felt better and we all went on a walk to get out of the classroom before lunch. I feel very comfortable asking for help when I need it or when I don't feel adequately prepared; I will continue to do so in this new role."