How to get an iPhone out of recovery mode without iTunes and no lock button?

My iPhone's lock button doesn't work and i got it in recovery mode. I tried using iTunes but it'll send me there was an error.

Is your iPhone jailbroken? If it is then uninstall last tweak you downloaded from cydia or all the tweaks.
Cause of this problem is that some of your tweaks has crashed. After that just respring ( restart springboard) or tap the clock at the top of screen and tap respring.

Download Tinyumbrella

Open the program

Click "Fix recovery"

Your phone will be kicked out of recovery and back to normal again.