Brief Answer:
A respiratory tract infection probably

Detailed Answer:
Hello,

sore throat and cough are commonly caused by respiratory tract infections. Most of the are viral.
If you've got fever then clinical examination is needed to exclude the most serious diagnosis of pneumonia.
If no fever is present then you can wait for a few days and everything would be better. If you've also got malaise and fatigue, you can use paracetamol to make you feel better.

I hope I've addressed your concerns! If you need more details, please use your follow-up questions, to specify them.

Kind Regards!

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Brief Answer:
Sinusitis is a concern

Detailed Answer:
Hi,

mild upper respiratory tract infections can be complicated by sinusitis, which causes worsening after an initial improvement of the symptoms. This is usually accompanied by headache. In the most severe cases antibiotic treatment is indicated (when fever or severe symptoms are present).

Kind Regards!

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Brief Answer:
Antibiotic treatment might be needed

Detailed Answer:
Hi,

if your symptoms are bearable, then you can try nasal corticosteroids and nasal decongestants.
If your symptoms are severe enough, then antibiotic treatment has to be added to the aforementioned regimen.

Best wishes for a speedy recovery!

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