Have only had it for 4 days and won't turn on today. I have a suspicion that the charger may have been damaged so maybe battery is just dead and won't charge. Yesterday I went to unplug it from the wall and it came apart. Is this normal for the round disc part of the charger that the usb plugs into and then into the wall to come apart it two pieces? I just snapped it back together so thought it was ok. Anyone know if this thing is supposed to come apart?