Brief Answer:
It might be a symptom of mild viral infection.

Detailed Answer:
Hi...
Welcome to "Ask a Doctor"service.
I am Dr Ajeet XXXXXXX

I have gone through your query and here is my opinion.

Kindly share your age,status of your body weight and co morbidity (if any)specially diabetes mellitus.
Has your thyroid levels been checked in the recent past?

Many people describe these symptoms as an "internal fever where you feel feverish and have malaise and lassitude but thermometer records no fever.
This may be due to an emotional cause, such as severe stress or anxiety,after strenuous exercise or during an ovulation period of a fertile female (14 days prior to the next menstrual cycle).
In such cases, the feeling of raised temperature weans off after some time.

At times,this feeling is there just before the onset of a viral flu.

Keep yourself well hydrated,take nourishing diet including plentiful of vegetables and fruits and take rest.Avoid sleep deprivation and de stress yourself.
If the symptoms do not improve,please visit your clinician for complete evaluation and clinical examination.

Hope that I have answered your query.

Stay healthy and stay blessed.
Regards.

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Brief Answer:
It might be a symptom of mild viral infection.

Detailed Answer:
Welcome back.

As per your nerration,most likely it is an onset of mild viral flu.

A viral infection might be mild,moderate and at times severe in intensity.

It usually has an abrupt onset and presenting symptoms may range from feeling feverish,feeling bad,high fever,headache,chills,cough,blocked nose,throat pain,nausea,vomiting,body pain,easy fatigue to irritability.

It is also worth noting that all flu patients will not have a full blown fever.

Regards.

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Brief Answer:
It might be a symptom of mild viral infection.

Detailed Answer:
Yes ..... It is quite possible.

Happy living.
Warm regards.

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