In an insane asylum. They tell you that you are there because you are having hallucinations and telling people you are from the future. Your parents are children, your grandparents are young adults and none of your friends or siblings have even been born yet. Write about who you convince the doctor that you are not insane and to release you without getting a lobotomy, electric shock therapy or being heavily sedated. Bonus writing topic: how you use your knowledge of the future to alter history once you get out.