Okay, i'm sure this is nothing.. but a while after i plug the charger into my macbook the light goes off, it's still charging, but with no light. If i take it out and insert it back it goes on for a while again, and then off. This happened recently, the macbook is about.. 6months old. Should i be worried or is this just a random thing? I don't want my macbook to go up in flames 