I am glad you posted this, becasue so many have said the opposite. I am 100% normal upon waking and the day goes fairly well (unless I am under artiificial lighting or have typical triggers..like talking too long to people) but slowly building up with symptoms until about 4 PM, when I turn into a pumpkin. The symtpoms do not abate usually until I go to sleep.
One of the many medical communitys attempts to solve this for me was a "hypoglycemic" all day sugar testing, for many peeps blood sugar goes down at this time. But of course I was normal. Most people do experience this low time during late afternoon, but my symtpoms are heavy dr and then dp, not jsut some low level fatigue. I often have wondered if anxiety..as it builds up during the day...kind of limits out in te body and the body gives up. But what is so strange is that this 4 pm start happens no matter if I at work or play, walking in the woods or shopping, stressed or totally at ease. It is always comes
anyway.
jft