I occasionally hit these moments when I am trying to both process what needs to be done while trying to do something resulting in nothing being done. It is these times when I break down into creating a short list. Not a long list but a short list. Making sure that one of those items is something that needs to be done.
Just the process of focusing on the next 3-5 tasks helps me start moving in the right direction. In addition we often do not celebrate or acknowledge the small step or task. This also becomes a problem regarding self achievement and self-worth. If you do not acknowledge each step you may find yourself so depressed at non-completion you never get to the end creating a self fulfilling prophecy.
That being stated. I am writing the next 3 tasks down and just completing them. POST DONE. lol