Alright. You are not crying. You are not freaking out. You are not a thirteen-year-old girl anymore. You're you again, and even a refined and improved you, but you've suddenly realized that magic actually exists in the world.
After all, it's not that normal to wander into stranger's houses through the open French doors, and it's even more not normal to take your clothes off and parade around in front of their mirrors in your boxers and muscle-T. Transforming into a girl and back was even more not normal, but in the balance, you realize you've come under a spell and somehow been led here.
You're not certain if this is the witch's shopping emporium or what, but you decide that you like what the mirror you've found does and don't really want to play with any of the other mirrors in the hall, since they might start talking or opening doorways to other worlds or having your reflection step out or any of a dozen other things that magic mirrors are known to do. You? You've hit the jackpot.
Of course, the mirror in front of you is about eight feet high and four feet wide with a heavy gilt frame, so there's no way you'd be able to carry it. Unless...
You picture yourself as you, but magnified. Taller, wider, with huge arms, and even huger muscles, with giant hands able to grasp anything and huge feet able to support your weight. The image in the mirror shimmers, and then you're looking at yourself, built like a tank, half as wide as you are tall, and you're actually stooping to look at yourself in the mirror. You're a human tank.
However, you're also big enough to lift the mirror down and carefully carry it out the french doors and across town to your place. You get a lot of stares, since you're a giant carrying an antique mirror that you'd usually need professional movers to carry, but you get it home and put it in your garage.
It's there. Your magic mirror. Not broken or anything.
It's kind of fun being the size of the Hulk, but you realize that it may get old soon, so you picture yourself as something more reasonable. Say 6'9" with a runner's build.
Nothing happens.
Maybe it wasn't the mirror that was magic? And can you find your way back to the mysterious mansion?