Just a few days ago my battery on my phone drained to 0 then charged it while turned off. But something suddenly came up and I need to go immediately and plugged the charger out before it was full. After that, my battery can barely last 1 day but normally my phone lasts up to 3 days without wifi and I already have Juice Defender and I actually upgraded it into Ultimate. So, what can I do about this? Do I have to buy a new battery or does anyone have an alternative?