iPhone 4 Battery Issues

[iDeviceHelp24]

First of all im new to these forums but i have an iphone 4 on 5.1.1 and jailbroken but i recently noticed something wierd yesterday i wne to sleep around 3:30 am and my iphone was at 98% with wifi turned on and i woke up at 12:30 and its was at 88% and five sec after looking at the percentage it went to 87% this is the first time i noticied rhis it has never happened to me and ive been jailbroken on the same firmware BTW ive also turned off all bluethoot and locationes push mail notifications icloud and dim the screen to background apps and then i fully charged it again @ 3:00 pm and by 5:00 it was @ 77% why PS i let my iphone battrry completely die everyday