[violetpretty]

I think it depends on how you present the information. If you say "Oh sorry I'm so quiet/awkward, I have social anxiety disorder," that would be weird, and like KSUViolet has said, the general population does not know what SAD entails. Explaining SAD thoroughly to each member you speak with won't really give them a chance to get to know you in 10 minutes, you'll just be "the PNM who has SAD".

However, you can mention when a member asks you why you want to go Greek that you are shy and sometimes feel socially anxious and are looking to come out of your shell and blossom. In other words, I'd use adjectives to describe your condition rather than the "diagnosis".

One really helpful thing you can do to help you feel more relaxed is to come up with "backup questions". Although the members (IMO) should be responsible for guiding the conversation and trying to learn information about you, not everyone is great at recruiting, and sometimes there will be lulls in conversation. If you can think of a few questions to ask if/when there's an awkward silence, you should feel more at ease.

I'd recommend asking your rusher about her experiences in her chapter. Ask about her favorite memory from her new member period, about her big and/or little, about her position if she has/had one, if she lives in the house (if your school has them)/what she likes about it, what else she does on campus/how she balances her time. These questions are more personal than "what's your philanthropy" (especially since they will probably tell you that in one of the rounds anyway) and not obscure like "If you were stranded on a desert island..." Asking questions about a member's experience will also give you a chance to express specific things that interest you about sorority life.

Good luck!