Setting a goal is good but taking it day by day is a must. I think we underestimate ourselves with the unknowns of fasting with our bodies so we short change and only go a day or two. It is good if you can squeeze “one more day” out of a fast, as long as you listen to your body. That’s how I got from a 3 day to a 5 day to a 7 that finally ended on 9 days.
Keep it up, I’m on my third fast on day 4 and I feel great, much easier once you’ve done it a few times.
I’m currently on the morning of day 2 and am surprised how easy it’s been so far. I’ve always eaten pretty sporadically (never been a 3 square a day man) so I think that helps. Aiming for 5-7 days but will see how it goes. Great work man, keep it up and hope your back gets better soon!