Looks like an issue with spacing, probably the tabs (using show/hide code button in paragraph section of ribbon to show formatting would show arrows for tabs). Notice how the spacing after the headings is the same for paragraphs that have the same heading level. For example, level x.x has one space after heading, while level x.x.x has no space.
You have to adjust the tabs after each heading. From Microsoft Website:
modify table of contents
To change the way heading levels are displayed in the table of contents, >click Modify. In the Style dialog box, click the level that you want to >change, and then click Modify. In the Modify Style dialog box, you can >change the font, the size, and the amount of indentation.
Hope this helps.