Why do page numbers no longer work for me in Word 2010?

So, I was happily writing along for National Novel Writing Month and had just hit the 5000 words mark. I started a new chapter, and bam! None of the page numbers show up any more! Where they ued to be, there is just a blank space! I had them formatted so that they went “Chapter-Page” so that if page 20 was part of chapter 3 it would say “3–20” for example. In my table of contents, it shows each chapter as starting on “1–0” and “2–0”. Does anyone know what I can do to help with this? Thanks.