Because you’re not eating, something that takes up an inordinate amount of your day, one tends to fill the space by focussing on smaller things one wouldn’t normally notice and they become more prominent or noticeable than they should or normally would. Think of the time taken buy mealtimes, thinking about meals, shopping for meals, preparing meals etc etc. It’s a huge part of a day. Just chill and relax or distract yourself with something. It will soon pass.
When your body starts getting really low on your stored carbohydrate resources and before it switches to ketogenesis, your mood will usually drop and you can get a headache and have low energy. For me this happens at the end of day 2. Some people my have some tips on how to combat it.
Fasting can be a grind. You’re sipping water and waiting for the hours to pass and it can be a lot. I get pretty impatient and a bit grouchy so I do my best not to deal with people. It can be challenging when I have to work the same time as fasting. But I try to keep in mind my fasting goals and it helps.
Definitely. I am an experienced faster and often get irritated and fatigued during fasting. Some fasts are terribly hard, others are fairly easy. It’s usually hardest at around 16-22 hours fasted in terms of mood, for me anyway. But sometimes I sail through the first day and get cranky on the 2nd. I usually only fast 24-48 hours, but when I do go a 3rd day I am very low energy at that point, but less moody. Couch potato mode.