What you're experiencing is that you've removed the whitespace between the toolbar on top of the page and the page itself.
You can fix it back if you rest the mouse pointer over the gray area above the page (b/w the toolbar and the page) and then double click when you see Double-click to show white space.
You can also do this to make a button appear on the quick access toolbar right of the Office button for a faster access:
1. Click the Microsoft Office Button, and then click Word
Options on the bottom.
2. In the left pane, click Customize.
3. In the Choose commands from list, click All Commands.
4. Click White Space Between Pages, click Add, and then
click OK. The White Space Between Pages option will appear on the
Quick Access Toolbar.