Jailbroke at 3.1.2, and the phone was working fine until it slowed down a bit after a call. I turned it off and now it won't turn back on. Been jailbroken for at least 6 months. All that happens now is the pineapple will come up for about 5 seconds, then disappear. Even when I plug it into the laptop, it does not start charging, and the computer doesn't see it. Help?