"I almost couldn't come in to see you," your twenty year old female patient tells you. "I mean, since I was 14, I've been so shy. It's just part of my personality, I think, but I just get so afraid that someone will talk to me when I'm on the bus or something. I can't go out to a restaurant, I can't go to a party, I don't like being in small groups of people. What if someone I don't know talks to me? Or is looking at me? What if I do something stupid or embarrassing or humiliating? Even talking to you, doctor, makes me really nervous. Like, what if I have to use the bathroom? I can't use the bathroom here; it's a public bathroom. Or maybe you have one of those single-person bathrooms in your clinic, that would be good for me. I mean, I know it's silly, but I just get so anxious when I think about it. I haven't been on a date ever. I can't imagine talking to someone. I'd get so afraid. I don't think I have symptoms like palpitations or anything, I just feel terrified. So I avoid situations like that and if I have to be in one, I try to get out as soon as I can."
Challenge: Obviously, this falls within a spectrum of disorders, but pick a diagnosis.