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headache and tiredness can be symptoms for quite a few disorders.
However the continuous work/engagement over the laptop for the whole day can also be blamed for her tiredness and the headache.
If using the laptop is an important task then this tiredness and headaches can be managed by cutting the routine in to small pieces of 5 or 10 minute breaks every 30-40 minutes. This should be particularly helpful with the headaches as she wont be continuously concentrating on the screen.
The most common medical conditions for tiredness and headaches can be Hypothyroidism and diabetes. The headaches and tiredness can also be due to weak eye sight where the person has to exert more than normal while working or reading on the laptop or a book.
However considering her age and her routine this most likely is the over work than any medical conditions that is to be blamed.
Hope This Helped :)
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