Did you include the "CONTENTS" title as part of the text in that document? Does it have a style applied?
It's hard to tell from just the ebook screenshot what's caused the issue. If you could create a sample project demonstrating the problem and zip and upload that here, or send a zipped copy of the original to firstname.lastname@example.org (Attn: Jennifer), I can take a look at the editor and compile settings in the project. The tutorial you linked has minimal instructions, so it's hard to guess from that what you may have ended up with (for instance, it doesn't deal with the compile format or section layouts, and what you have set for your "Contents" document will affect how it looks on compile).