Brief Answer:
need some further details as well as evaluation regarding...

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

Well, this can be due to several reasons. So, could you kindly let me know a few more details about it first?

-Your age, gender and occupation, please?

-Kindly elaborate what do you mean by "stamina"...Do you mean to say your lethargic/sleepy, having any difficulty concentrating on work, loss of appetite, extreme tiredness during any specific time of the day?

-Since when is this happening?

-Have you undergone any health check-up or investigations lately? If yes, how were the reports? You can also upload them here to the reports section so that I can review them in details...

-Are you on any particular medications/diet due to any particular reason?

-Any recent history of any particular disease?

Kindly elaborate your concern in a bit more detailed fashion so that I can guide you specifically...

Wish you a good health...

Take Care
Kind Regards

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