No, it is not possible to manifest anything overnight. Manifestation is a gradual process that takes time to see the desired results. You must allow the universe to take its time to work things out in your favor.  You cannot get clear skin overnight, but you can change what's within you. External change takes time, but you can change your internal thoughts overnight by eliminating mental manifestation blocks.  While the universe helps you in the healing process, you must have faith, keep your vibrations high using affirmations and visualization, and take inspired action to make it happen.