I recently had an interview at a highly selective college. This college is my top choice. I had something very embarrassing t happen to me during the interview. What should I do?
I bet it wasn’t as big a deal as it felt to you! You probably don’t need to do anything; just email the interviewer and thank him/her for his/her time as usual and don’t even bring it up.
But, okay, I’m super curious. What was the embarrassing thing that happened?
Unless you vomitted on the interviewer, it is already forgotten. Even if, at least they’ll remember you;)
I had an erection in front of my female interviewer when I stood up to shake her hand.
Well now you have to tell us what happened…
It would not even occur to me, were I an interviewer, to look at the interviewee’s crotch. She might not have even noticed. Let yourself relax!
Even if they did, sometimes pants just look “that way”. Don’t worry.
I saw her eyes looking down.
I’m sure the interviewer would just dismiss it or barely noticed, you’re probably stressing over it more than you should. Worst case scenario…she knew you were interested 
…in the university/college of course. (Just trying to help lighten you up)
No worries! Women often become quite sexually liberated while at college, if they weren’t already during high school.
This is very likely no big deal.
You don’t know that she noticed, but even if she did:
If she thinks anything of it at all, she probably chuckles a bit at your misfortune. It’s involuntary, after all; you could not help it. She may thus even feel a bit flattered.
well at least I guess she knows you REALLY like that school
Easily my new favorite post on here.
Yeah definitely don’t do anything about it or include it in your thank-you email. “Thanks so much for taking the time to talk with me about your university! P.S. Sorry about the erection!” Yeah, no.
But seriously don’t worry; you’ll laugh about it in a few years. When your kids are freaking out about applying to college, you can tell them this story to ease their worries. Heck, you can even tell it to your grandchildren with a distant gleam in your eyes as you think back fondly on the days of yore.
“Heck, you can even tell it to your grandchildren with a distant gleam in your eyes as you think back fondly on the days of yore.”
And thus forever scarring your grandchildren.
You probably were her most enthusiastic interview for some time.
Relevant: http://youtu.be/63CBo7Z83-Q
Don’t worry, I doubt she noticed or could tell. But remember for future interviews it’s best for a successful interview to be focused more on what is being said than any other thoughts! 
Wow it must be a good interview!
Say, I think I heard something that might explain your predicament in the news a while back.
Were you applying to Fasttrain College in Miami perchance?
http://www.miamiherald.com/news/local/education/article4260601.html