Originally Posted by frankz
On a lot of Android devices, 0% is really about 10%-15% to prevent physical damage to the battery. Don't know if the Fire does that as well.
Yes, this is common. The cells themselves should never be discharged too much or charged too much - but the devices enforce that. Obviously you shouldn't continually keep using up juice by spending a half hour trying to turn it on when it tells you it's too low to turn on - but the presence of that message is evidence of its own protection!
Go ahead and run it till it turns itself off. But I doubt this will help you. Because you said the light comes on brighter when it's really charging, it sounds like you have a small physical short and you'll need a replacement.