Battery life remaining below 10% IIRC. The battery icon also will show red when it's this low. Definitely time to charge!
I don't know. Was the phone off during that time?
It’s an iPad. And it was on during that time. It was low on charge, below 10%
It means that battery level was at 10% or below, much like the battery icon in the status bar does.
Nothing to worry about.