Oh, I feel your pain, Celey ! (I think there is a shared pool of it out there...actually more like an ocean
) Have you ever seen that Dilbert book, "Still Pumped From Using The Mouse" ? It just occurred to me just now - I am the opposite, I am feeling tired just from using the scroll button on the mouse !! Days like this, I suddenly lose muscle tone with no notice, cannot clench a fist without my arm feeling like it has hypothermia, can't sit up straight (what I call "puppet strings" because I'm like a puppet with loose strings) and just feel totally cream crackered. But I was just on the phone to two friends and I was amazed at how normal and happy I sounded. It was like we were in parallel universes, with just a little one way window from mine to theirs.
But I know it ain't always so.
Ne Ne, days like these for me are now the rare exception rather than the rule. Some fatigue is normal, yes. I have to watch what I eat all the time, must have enough vitamins and Essential Fatty Acids and probiotics and electrolytes, but most of the time, eating fresh enough food and making sure I don't do too much physical activity will keep me from going back to square one like this. And now that I know what I have to do, recognise what is coming, what foods or lack of foods help trigger it, I get back to normal much faster than when I was ill first of all.
It's just my opinion, based on my own personal experience, but if you have not already been on an exclusion diet to see if that is part of your problem (eg gluten, dairy, eggs) then that might be well worth trying. It's not a magic pill, but it can work wonders.