Seems like you’re already rooming with someone you don’t know other than being a familiar face from your HS.
You agreed to be a roommate with this person. Backing out at this late date would be an unkind thing to do. If you don’t like the dorm and have an opportunity to switch, discuss it with your roommate. If she agrees, then do that. If she doesn’t, then maybe that’s an invitation for you to pursue other roommates.
This is confusing - what is their criteria for requesting the change?
A roommate is a person who shares your room. There are still plenty of opportunities to meet as many new people as you want.