When dealing with pagination if there are 20 items per page but only 4 or less items on the final page then show the last items on the previous page. Paging forward just for a couple of items is a waste of time and resources.
The same principle applies for dynamically hiding or showing extra text in a blurb. If there are only a few more characters or words hidden by the ellipsis or 'show more' link then simply show them as part of the main text. The amount of text being hidden, which requires a click or page change to view, should be worth employing the extra time, effort, and resources to view. I'm often disappointed to click on a 'read more' link to only show another half a sentence or less (Facebook!).