Thanks for consulting. I have carefully worked through your case, and I can realize your health worries. Being your physician, I assure you not to worry as I will take care all of your medical concerns. tiredness at this age can be commonly due to diabetes. so check your blood sugar levels and rule out diabetes. other the thing might be dehydration. drink plenty of water for it. see to it your mouth never goes dry and urine never dark color. also some vitamin and micro nutrition deficiency can cause tiredness. so take a diet rich in green leafy vegetables and fruits and milk. Hope it helps. If you need further, detailed and quick assistance related to any health issues in future, feel free to ask me a question directly from my profile. Have a wonderful time ahead. Best Regards! Dr. Arunmozhi varman