Adulthood is an illusion we tell ourselves when we need to feel big and important and in control. Like all illusions, there is value in using it correctly. Masks and illusions aren't lies, they're simply shifts in perception. To see yourself briefly as an 'adult' is only possible because you have some of those qualities inside of you.
It's important to let yourself just BE, and to keep your adulthood mask something fitting of the real you, and not a reflection of expectations.