hi i have upgraded my samsung galaxy grand 2 to 4.4.2 last night, after that i charged it to 99% and went to sleep and unfortunately i kept my device under my pillow, next morning i found my cell overheated and showing only 20% battery remaining so i want to know what is his problem and how to solve this, now this kitkat is really sucking my battery like hell please help me plzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz.