I used to have the same thing
Hi,
I had the same problem years ago, and had to change my eating habits because of it...
Carb rich foods,such as whole grains,certain fruits,and some veggies contain fiber which can add bulk/density to your system, that can leave you feeling bloated and tired. Sometimes that added bulk from the carbs doesn't get broken down into energy. Carbs are healthy, but should be used in moderation by most us. Try eating smaller portions of carbs throughout the day, instead of all at once during one meal. You might also want to research online 'Carbohydrates and the Thirds Rule'. The Thirds Rule can give you some ideas about what to pair carbs with during mealtime.
Good Luck