Brief Answer:
Different reasons for tiredness.

Detailed Answer:
Hello dear, welcome to Ask a doctor service.
I read your query and here is my advice.
There are several reasons for fatigue and tiredness.
I wanted to know if you have recently suffered a viral infection like flu?
Have you recently done blood work?
Anemia often gives fatigue
Also low thyroid ( Hypothyroidism) causes tiredness.
If you are a female at reproduction age pregnancy may be a reason for tiredness.
Please tell me more details.

Hope I have answered the question.
Let me know if I can assist you further.

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Brief Answer:
Do a blood test.

Detailed Answer:
Hello again, did you took any medication to treat cogniuctivitis?
If it went by itself in 5 days without medications it had viral origine most probably.
The post viral fatigue syndrome is one of the main causes of fatigue.
There is no specific treatment about it.
Only yoga, exercise, acupuncture, pain killers may help.
Remember to do a blood work to get tested for anemia, diabetes and hypothyroidism.
Best regards

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