Brief Answer:
The flu probably but can't be sure

Detailed Answer:
Hello,

influenza's main characteristic is the sudden onset of high fever (sometimes with rigor), sour muscles and fatigue. The common cold is usually an afebrile disease but sometimes a low grade fever can occur. Common cold requires a runny nose and nasal congestion for the diagnosis - this is its main characteristic. Influenza on the contrary can present even without nasal symptoms. Sore throat and irritating cough are common symptoms in influenza.

In otherwise healthy individuals common cold is a very mild and self-limited disease that should not pose worries to the patient.
Influenza can be anything from mild to severe. Sometimes influenza can be complicated by pneumonia or (very rarely) other serious consequences like myocarditis etc.

So her case sounds more like a mild influenza disease than the common cold but other viral or bacterial infections could cause the same clinical picture.

Theraflu helps with fever, nasal symptoms and malaise. Influenza or the common cold won't last less with theraflu. If it's influenza then antiviral drugs can be used. Starting antiviral treatment within 48 hours after symptoms initiation is required to achieve substantial improvement. Common cold has no specific treatment. Only symptomatic treatment can be tried.

So the answer to your question, is that clinical examination is needed to exclude a complicated influenza scenario. In most cases though, both diseases follow an uncomplicated self-limited course without any concerns.
"Red flag" signs include pleuritic pain, shortness of breath and low blood pressure. Also note that high fever that won't improve after 3 days, needs investigation anyway, unless the diagnosis has been established.

I hope I've helped!
If you'd like further information, please let me know.

Kind Regards!

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Brief Answer:
You're welcome

Detailed Answer:
You're welcome.
Thanks for asking!

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