When I'm at work I always feel tired and have headaches what could be the cause of this. I always sleep early if I'm going to work the next morning. Please help any suggestion comments or advise

Low iron, anemia.
Other nutritional deficiency, lack of vitamins, minerals, protein.
Food allergy.
Dehydration (coffee and tea don't count as 'hydrating').
Eye strain at your job.
Stress at your job or in general.

Those are the most common suggestions - we know NOTHING about you, your age and gender and weight and history and family history! And so on...

I agree, stress and worry about your job is my first guess, without knowing anything else.

Low iron, anemia.
Other nutritional deficiency, lack of vitamins, minerals, protein.
Food allergy.
Dehydration (coffee and tea don't count as 'hydrating').
Eye strain at your job.
Stress at your job or in general.

Those are the most common suggestions - we know NOTHING about you, your age and gender and weight and history and family history! And so on...
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maybe you are right about food allergy because last month I went to see a doctor and she gave me allergy pills. I'am 24 years olds Male weighing 92kg,My family none of them have had any seriously disease except myself when I was still a child I think 2 or 3 years I'm not sure they told me that I was sickness I don't know the correct name for the disease but I would just stop breathing, collapse sort of death but I got cured by a sangoma and it never happened until today and recently my GF had TB

I agree, stress and worry about your job is my first guess, without knowing anything else.
================================================== ======== I don't think its stress I'm enjoying work and personal life it's just perfect at the moment. See reply to joypulv