Why is my phone stuck and not useable after "yes" to upgrade (iTunes - didn't want)?

[iMore Question]

Mistake made, didn't want iTunes upgrade. Phone is stuck and cant be used. It has iTunes logo, a graphic of connector cord, and words "support.apple.com/phone/restore.

 

[nikkisharif]

That means you need to connect it to iTunes then follow the instructions on your computer.