I feel tired all the time, don't seem to have an energy and always seem to be ill if there is flu going around I pick it up. I can't exercise as much as I use to and I am still tired.

You need to be evaluated by your doctor. Fatigue can be caused by a number of things including but not limited to: anemia, thyroid disorders and vitamin deficiencies. If you are not vitamin deficient taking vitamins won't help your fatigue.

You need a proper medical diagnosis for your particular problem.