Troubleshooting Kindle 4th gen touch, stuck and won't turn off

[Rinsknife]

Hey, I got redirected to this forum so I apologize if I'm not doing things right or if this place ends up being pretty dead.

Anyways, I got an amazon kindle 4th generation touch. Recently I wanted to see if I could get custom screensavers for it. It told me to install a jailbreak, which ended up working. But when I wanted to find how to turn off the menu and return to my books, the thing completely got stuck. So now it's stuck on the jailbreak menu and I can't turn off my device or connect it to my pc. I'm not sure if maybe I need to hold the power button for a really long time? Longest I've done before my hands hurt is 2 minutes.