I am sorry you are not feeling well.
It sounds like you have a viral upper respiratory infection given the sore throat, mild cough, nausea and nasal congestion.
What I would do at this point is continue with the Zetron and the paracetamol.
I would also start an over the counter cold medication such as sudafed
to help with the nasal congestion.
You can use a nasal saline spray to help clear up your nose as well.
Steam/humidified air will also be helpful for the congestion.
Your throat may be more sore in the morning due to breathing through your mouth. Since your nose is so stuffy, you may have only been mouth breathing last night.
If you are getting worse, develop a fever of 101 or more, develop shortness of breath or severe headache I would see your doctor.
Otherwise, this will likely last about 5-7 days.
Feel free to ask any follow up questions,
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