How to cancel an iphone update?

I recently decided to update my iphone. It told me to connect to iTunes, and I did, and now it is telling me I have to restore my phone completely to even connect to iTunes. I do not want to do this because there are many important things to me currently on my phone. I tried to hold the home and lock button to restart it, but it just brings me back to the screen that tells me to connect to iTunes. Is there any way I can just cancel it completely?

You don't need iTunes to update. You can do it via Wi-Fi. Your phone tried to update and got stuck in recovery mode.
Hopefully this will work. And remember to backup and sync with iTunes ever so often so this won't happen again. Best luck.