Brief Answer:
Flu...

Detailed Answer:
Hi,

The symptoms you described including fatigue, nausea and dizziness are consistent with seasonal flu infection. Since when are you having the problems?
The problems usually settle down in a few days (commonly within a week). During this period of recovery, you can start symptomatic treatment - tylenol cold and flu tablets along with steam inhalation and antacid medications.

If the problems are more than a week old, then I will recommend you visiting a doctor nearby for clinical examination and evaluation. Antibiotic therapy may then be necessary.

Hope this helps. Let me know if you need clarifications.

Regards

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