Brief Answer:
since there's a sore, you need to get yourself clinically examined by an ENT without any delay

Detailed Answer:
Hello XXXXXXX Welcome to HCM,
I've gone through your query and understand your concern,

Since you've pointed out the sore in your left nasal canal , let me inform you that you need to be clinically examined by an ENT at the earliest for this (under direct vision), there can be certain possibilities (starting from nasal polyp to nasal turbinate hypertrophy due to allergic manifestation, infection, ulceration and several others), it's extremely important to get yourself examined by the ENT specialist at the earliest for the exact diagnosis..management will be based on the findings.. the runny nose can be part of the associated allergic manifestation and/ infection..

Meanwhile you can take steam inhalation three to four times a day and ensure to remain well hydrated by drinking a lot of XXXXXXX warm liquids (soups, porridge etc.) and water..

Don't delay anymore get yourself checked out by the ENT specialist at the earliest.. please don't take any unsupervised OTC medications till get the exact diagnosis..

Let me know how you stay in the due course..
Take Care
Kind Regards

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