Have your page numbers gone wonky? Does your document look great up to page 15 but the next page is 25, then 32? This is probably due to midpage sections.
If your page numbers were added to a header or footer that did not link or inherit from the previous header or footer, it is likely that some continuous section breaks were inserted in the middle of a page. If you can’t remember doing that, check to see if you set up selections of text in multiple columns. By default that creates sections.