I just discovered that I used the wrong keyboard shortcut while writing, and a bunch of what should have been footnotes are comments. Is there an easy way to convert them as a group, rather than manually?
No problem at all! Select all of the rogue comments in the inspector sidebar (you can use the Shift and Command keys to select groups, just like you would select multiple items in the binder), right-click on the lot of them, and you should be able to figure it out from there. 
Thank you, AmberV, it worked and I got everything cleaned up in a few minutes! 