trying to update to iOS 7.2... NEED HELP

ive been trying to update my iphone 4s 16gb to the new ios 7.2

ive passed through the first load screen but the phone has now frozen/locked halfway through the second load screen

(theres just an apple logo and a half loaded bar) i havent been able to use my phon for over 12 hours now.

some friends have suggested i try restoring a back up from icloud and from my computer and if worse comes to worst restoring to factory setting

but itunes wont allow me to do either as it says the phone is locked with a passcode (have tried all 3)

my lock button on the top right hand corner is also not working so i cannot even hold doen the home button and lock screen to reset/turn off

can anyone help???