Just ask your family Dr. they shouldn’t roll their eyes at all. Both Drs. I asked (I moved) were more than willing to test after I told them how almost lethargic I was.
BTW, if they do roll their eyes it might be time to find another. I have asked some out of the world questions about different things and I have been lucky because they have always been taken seriously.
Well, nothing to lose. Ask for levels of Vit D, Vitamin B12 and what else?
I supplement with 20K iu D a day and try to remember to take the sublingual B12 but usually have already brushed my teeth or I forget and start chewing them :-)