My phone drains very quickly, without anything happening. When I go to sleep with a fully charged phone, I wake up with it dead. The puzzling part is that when I plug the phone in, it immediately says that its 90% charged, and allow me to turn it on. But a few minutes later, it will drop back down to 3% or so and then die soon after. Its a samsung galaxy Ace and I've had it a little less than a year, but this has been happening the past few weeks. What's going on?