i have a 2012 13' 128gb Macbook Air. I haven't had any issues until now. I'm running out of storage very fast and I don't know why. I have 12.27 gb in Movies, 9.54gb in audio, 8.11gb in apps, 4.85gb in photos, and 8mb in backups(which is all pretty normal). But then I have 57.29gb taken up by...