Change me back!(Hetalia reader)

In this story, you're the only girl in your family. You have four brothers. Alfred(America), Arthur(England), Francis(France), and Mathew(Canada). One day, Arthur was acting very weird and your concern lead to you being involved with his magical experiment that goes wrong. Very wrong. Somehow, you end up body switching with Gilbert(Prussia). How will you get back to your body before Gilbert gets to your vital regions?!