I’m exhausted… 
perhaps its also got something to do with the fact i wake up at 5…i start work at 7.
Yes probably. What time do you go to bed? How well do you sleep at night?
But yes - vitamin D and iron deficiency can both increase tiredness:
I use both Vit D and Melatonin to fight fatigue and regulate my sleep cycle. I used to use caffeine, but am now caffeine free for just over three weeks. Completely free. Having fewer problems with wanting to fall asleep while I’m driving.
10-96
I get roughly 7-8 hours sleep …
If you have been up and down with moods the last few days you’re most likely emotionally exhausted. Not sure what to do that does help but does pass with time. As they say…If pain persists see your doctor.
I have a vitamin D deficiency and supplementing with D3 - I do tire rather easily, but this could be from other factors, like low testosterone levels, lack of good nights sleep, Diabetes etc…
Were you tested for a vitamin D deficiency? I would not conclude that your lack of energy has something to do with vitamin D levels - could be other factors involved
I complain of being tired all the time for the last 45 years. The doctors act surprised when I tell them that,
Jayster