Steve
Are you diabetic? - if so, what meds? On insulin thats a hypo and will need treated by fast acting sugar (sugar, full fat coke, lucozade, dextro tabs, fresh OJ).If on oral meds then it suggests that they are too strong, and if insulin its too much
If you are not diabetic, its prob still a hypo but not dangerous for you and you will feel better if you just have something to eat.
However, might be reactive hypos where your body shoots up and down in response to high sugar/carb food
Advice would be, watch your diet more carefully, or adjust meds if you are on them