My Iphone 4 wont go past the apple screen? Help!

Hey guys, I recently have jailbroken my phone, and was tryingto get Siri for my phone. I rebooted it, and now it wont go past. Even worse, I can't even turn it off! What can I do to fix this? Thanks

Version: 6.1.2

You've propably just blown a fuse, just put in the microwave or oven on light heat to makes sure the fuse melts together again.

Enter DFU>Restore to iOS 6.1.3>Wait for new jailbreak, and all your current settings lost. No other fixes. If the iPhone 4 dont get ios7, you probably will never be able to jailbreak it again.