Alright, need help.

[Flootershy]

My mother bought this phone about, 3-4 months ago? I have personal experience with Galaxy S's and most mostly all HTCs. but, I don't know. I guess my mothers battery might've fired over overuse, or car charger from what I read? A blue screen came on and it and just I guess, pooped. But I have no clue, I read about that you can reflash it, but here's the thing, I can't even put in into emergency mode, I tried the button combinations, I don't know if that's from the battery , or what. I just want to confirm everything, is it my mothers phone battery, or am I doing something wrong ?