I'm on day 2 and still standing strong here.
On this weekend though, I've been spending a lot of time researching and reading.
I notice my lungs, legs, head and stomach are cleaning up or whatever is going on, seems like it is clinching together.
Yesterday, something weird happened. My left hands left finger started beating like a heart beat (on just that location and only my left hand) for 20 minutes and then stopped.
You notice a much more increase in time though, after you've stopped eating.