Hi guys.
I've searched the forum, but I couldn't find an answer to this question.

I put my phone in the charger last night, and the battery was almost dead. It was in the charger for some hours, and it finished charging (I heard that sound it does, when it's done charging).
During the night it had found its way underneath my madress. So, when I pull out the charger this morning, I notice that the phone is really (!) hot, and all there is on the screen is an empty battery with a yellow warning triangle with an exclamation mark in it. So, I imagine, due to overheating, the phone has discharged itself completely. I couldn't turn it on, and decided to let it cool off and bring my charger to work.
I saw that triangle again, but after turning it on and off a couple of times, I got it turned on, and it's now charging as usual.

This leaves me with a few questions (I'm not really that into batteries and how they work and react):

• Why did the phone discharge? Is this a safety feature, or is it because the battery has taken a LOT of beating during the night?

• Should I be concerned about my phone having taken damaged?

Thanks!

EDIT: Yes, I know it's supposed to be "Has" in the title. I suppose I'm not fully awake yet..

 

Thanks for the response (and the jokes ), guys!
I have an update on the perfomance.

I feel that the battery is drained faster now than it used to.
But then, let's say it's got down to 13%, if I don't use it for like 15 minutes, it'll suddenly be up to 18% So it's like the battery thinks it's about to die (If I listen to music, read a book or play a game or something), and when I let it rest for a while, it regains energy.

Can anyone relate to this?
Certainly this is not optimal, and I hope the problem will solve itself over time.