You traveled back in time. (You came from the time where harry and the rest were at hogwarts) but all of a sudden you turned back in time, back to the marauders.

they all look up at you, when you suddenly spawned in their room "Uh hello?" -regulus "who are you?" -sirius "how did you get here?" -James "what happend?" -Peter "What" - Barty evan looks at you confused "well are you gonna explain?" -Remus