Procrastination As Self-Care

So I decided on a huge goal for myself, which at the planning and calendar scheduling felt exciting and I was all in.
The next day when I had to do it, my brain shrunk with fear in the corner of my head like a kicked dog, followed by few weeks of procrastination and great reasons for why the goal should be changed to a better one.
My brain is telling me that procrastination is nothing I should be ashamed of, and that it is a self-care mechanism. That because I scared my brain, it procrastinates in order to delay the frightening doing time.

How do I deal with this reasoning?