Hitting “F” to fill faces only creates an edge?

When I hit “F” to fill a face as shown in the video, it is only creating an edge. I’m guessing I have an open loop or something so the fill tool isn’t working as I expect it to? I’ve tried removing duplicates and making sure all the normals are pointed the same way, what might I be doing wrong? This is what I am seeing: http://g.recordit.co/JKlPibejQQ.gif