Respected user, hi I evaluated your query thoroughly.
*Usually 
hypoglycemia , dehydrated states , low 
haemoglobin levels give 
  rise  to the said symptoms.
@ maintain your hydration levels with plenty of liquids
@ keep your BP ,weight,  Blood sugar , 
Cholesterol levels under control.
@ check out your Haemoglobin level , visual acquity.
@ quit tobacco / alcohol / abuse substances of any form if using.
@ Diet rich in iron, protein , vitamins, minerals , anti-oxidants I recommend
    more green leafy vegetables, cereals, milk, jaggery , fruits for you.
@ avoid exposure to excess heat.
@ Light exercises at home with YOGA help tremendously.
@ avoid 
stress / 
anxiety .
@ have adequate sound sleep of 8 hours.
@ In case more difficulty you feel , go to ER & get checked by Physician.
 Hope this clears your query.
 Thanks for using Health Care magic & keeping trust in our services.
 Would love to assist in any future need.
 Wishing you fast and speedy recovery from the same.
 Regards dear take care.