Brief Answer:
Less likely...

Detailed Answer:
Hi,

Sudden episode of anxiety and stress induce certain physiological changes that may rise body temperature. However the rise is not significant and may not be noticable.

Classical symptoms of flu include fever of varying severity along with body pains, weakness. It is associated with symptoms such as nasal congestion, cough and sometimes loose stools and vomiting. These symptoms are not directly caused by anxiety or stress.

Hope this answers your question. Let me know if you need clarifications.

Regards

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