Have you checked to make sure that you are not hiding a home screen? If you press and hold on one of your home screens until the icons begin to "wiggle". Go down to just above the dock area, where the bottom row of icons is. You should see a series of dots, as shown in the first screenshot I've provided. Tap on that group of dots. The screen should change like the second screenshot that I provided. When you look at that screen, you will see an image of all your home screens with a checkmark below them. If there is no checkmark, that screen is hidden. Tap on it and the checkmark should appear, then tap Done in the upper right corner. If there was no checkmark, after checking it, that screen will appear again.


As far as what KiltedTim was saying about what were you seeing, if you hold an icon in the App Library, if it is not on a home screen, it would appear as what you see in this last screenshot. You can see the entry in the menu to add it to the home screen.
