Hi Deilla, it can be useful to take a vitamin and mineral tablet every day. But it can be useful to go through your meal-plan as well to see if there is some stuff you think you lack.

Here is a link to what the vitamins and minerals do to your body:

Vitamins and Minerals - HelpGuide.org

And here is a link to what kind of food that has those important vitamins and minerals. (Scroll down a bit to find the food section) :

The best foods for vitamins and minerals - Harvard Health

I am sure you know that both high and low blood glucose can make you very tired. Any kind of physical sickness or enormous stress will rise your blood glucose as well. Please contact a doctor if you find that you have too high levels of blood glucose for some days. That can mean an infection of some sort that needs to be medicated.

Of course you know that depression in itself can cause tiredness from time to time.

Hope you find out what is the matter and becomes better soon!