Hi thanks for posting your query. I have gone through your question .As you are having symptoms like pain on the back of head on exposure to sun or heat .The main cause of this problem is imbalance in pitta- vata dosha.The imbalance in hot pitta dosha due to exposure to sun or excessive stress,digestive issues manifest as a headache.The key is to follow the diet and lifestyle that will pacify vatapitta dosha. Diet Avoid pitta aggravating food in the diet like spicy,sour,tea,coffee,alcohol,eggs,non veg. Consume food which have cooling effect on body and mind like coriander,mint,amla ,aloe vera ,coconut water. Avoid heavy processed,frozen,canned food. Favor freshly cooked,organic foods. Lifestyle Avoid exposure to sun,heat,fog,cold ,wind. Eliminate stress from your life. Never suppress natural urges Walking for half an hour is helpful to keep digestion regular. Practise yoga to help increase blood to brain and relax tensions in mind and body. Yoga as an as and pranayam which you can practise are Anulom vilom,bhramri,udgeeth,bhastrika,sheetali,sheetkari,shavasan,yoga nidra,pavanmuktasan,sarvangasan. Massage your head with medicated brahmi oil. Instill two drops of Anu oil into both nostrils before sleep daily. Hot foot bath half an hour before sleep is highly recommended. Shirodhara is an effective procedure . Hope your all doubts are clear and you are satisfied with this answer. In case you have any query I am happy to help. Best wishes for good health Take care Dr.Pallavi