Update: I figured out that you *can* get just a list of your most recent photos with method=”search”… you just search for yourself:
[flickr-gallery mode="search" user_id="NSID"]
On flickr’s api page for the search method, they say you can use user_id=”me” to get your own photos, but that doesn’t seem to work in this case. You can get your NSID at https://www.flickr.com/services/api/explore/ (in case you’ve set your url to use your username instead)
Also, perhaps all of the gallery methods should accept a “size” argument in case you don’t really want the squares.