Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your complain sore milky white tongue seems to be due to Oral Yeast infection known as
Oral Thrush while the stuffing of nose and coughing up of phlegm and congestion can be due to
Sinus infection causing
Sinusitis..
You should consult an Otolaryngologist and get a clinical examination done and a PNS View of sinuses and MRI Scan can help in confirming the cause as well as clinical evaluation and microscopic examination of sinuses can help in diagnosis and treatment can be planned accordingly .
In case of Sinusitis you can be advised to take antibiotics like Augmentin, painkillers like Ibuprofen, saline
nasal spray, steam inhalation and steroid nasal spray..
Use a humidifier in your room..
For white coating you can gargle with Nystatin mouthwash and suck
clotrimazole lozenges..
Take more of Probiotics like Yoghurt and Garlic..
Hope this information helps..
Thanks and regards.
Dr.Honey Nandwani Arora.