Thanks for the answer! You are probably right about the iron and vitamin D, both were low last time I had some blood samples tested. Ferritin was 40 (10-130) and vitamin D 58 (75-150). The physician advised me to take extra D3, but no comment on the iron - though I see it is low.

Seems like I should also try again to convince her to let me take a cortisol saliva test. One year ago, she had me take a blood cortisol test, along with ACTH and aldosterone, who were all normal:
S-kortisol 07-09: 477 (138-690), P-ACTH 07-09: 5,0 (below 10,2), S-Aldosteron: 687 (70-800). I believe those tests don't give the full picture.