My friend recently has the same problem - missing "More" button at the end of the feed.
It is interesting that the earlier pictures are still in the feed. Simply access them by standard means impossible.
If the "more" button still does not appear, there is one way to bring old photos. If someone put "Like" to your photos - in their feed displays links to this photos. You can access to earlier pictures by clicking on this links in their feed.
See the example at the link below:
http://prntscr.com/6ptbm6