I've been using my 3GS for a few weeks now without any problems until yesterday morning. I woke and took out the phone from the charger after I left it on there at night and felt that it was a little bit warm, but I didn't really think about it. Then 3 hours later, I looked at the battery and it said 58% on there. All I did within those 3 hours was listen to music for 20 minutes, with no phone calls at all. Then, 3 hours later, my phone ran out of battery. I come home at night and charged it, but it became really warm. I took it out of the charger and the % was going down really really fast. Now, the phone is always really warm, even more so when I plug it into the charger. Battery is still going down like crazy. It's jailbroken and is running 3.0. I've never upgraded it to 3.1 before. What should I do now? Restore it or something?