IPhone 4 won't go to home screen and won't turn off or lock?

Okay so, my iphone 4 buttons work cause i can "take" a picture of what's on the screen.
i went to settings to do some things and then i tried to clik home, but it wouldnt work and it won't lock or power off Please Help my parents will kill me if its broken

Try restarting your phone:
Hold down the power button and home button for 10 seconds.
This should fix any problems, otherwise your problem is with the hardware.

Force a reboot.

Hold the screenshot buttons for ten or so seconds.