Feed in Sidebar

Hello,
The Instagram sidebar feed looks perfect for what I’m looking to do, but I can’t get it to work. I don’t see a “feed them social” option in the widgets panel and the short-code doesn’t work in the sidebar widget. Am I totally missing something or might there be a conflict with the theme (themetastic theme)? Lmk if you need any additional info. Thx

http://wordpress.org/plugins/feed-them-social/