I recently purchased a new macbook pro 13 retina 128GB SSD. It's my first mac and when I check how much storage is taken up in my personal folder (music/movies/doc/etc.) it's telling me that 25GB is in the folder. However, when I check each folder inside, they all say at most 2GB. Which makes the total WAY less than 25. Is there a hidden folder system that I'm missing?