Dorm bed HELP?!?!? Hi, I'm going to boarding school tomorrow...(summer program) its my first time....

Hi, I'm going to boarding school tomorrow...(summer program) its my first time. I heard to obtain twin extra long, but I only have today I'm departure tomorrow and I have no one to lift me to Kmart or Walmart or some other place...so I bought Queen size bedding...I know its gonna be wide but I'll just tuck it surrounded by the bed. I just wanna know if it will fit the length?...By the way does anyone know how long the twin bed are...PLEASE HELP

Also out of curiosity, why are dorm beds longer and thinner?
Updating interior of rented home, on the cheap-...
Answers:    yes it should be long enough. XL twin is 39" x 80" and queen is 60" x 80", so should be same length.
As for why dorm bed are longer and thinner-I don't think they're thinner. Regular twin is 39x75. Dorm beds would be longer to accomodate the different height of all the people who will sleep in that over time.
Hope you have a great time at school!