Waking Up at Hogwarts

Elaina is 22, and most importantly, a muggle. She fell in love with the Harry Potter books, and always wished they were true. When she finds herself waking up at Hogwarts in 1975 with no recollection of how she arrived there, she's confused but soon determined to change things... It would be a lot easier if Potter would stop shouting or Black would stop hexing Snape so much though.