my iPod touch won't zoom out

I think something similar happened to me. In settings-general-accessibility-accessibility shortcut-zoom it can zoom in on the whole screen. I would try triple clicking the home button, if that doesn't work try turning it off and back on, if that doesn't work either I would try restarting it (holding the home and power button)

You can also turn off zoom via iTunes:iOS: Home screen icons are magnified or large - Apple Support

Try double tapping with three fingers and also if needed double tapping with three fingers and sort of pinch your fingers inward to shrink the screen size. Once you get into the iPod, make sure you go to settings >general >accessibility and turn off zoom. -AJ