Brief Answer:
You need antibiotics and decongestants

Detailed Answer:
Hello,
Yes, this could be a sinus infection. Whenever there is a nasal and sinus infection the infected discharge drains back in the throat and irritates and infects the throat. The swollen lymph node is most likely secondary to sinus inflammation.

I urge you to visit an ENT specialist to start appropriate treatment. If I were to be your treating doctor after a detailed clinical examination, I would order for CT scan of nose and paranasal sinuses plain coronal sections only ,to see for extent of disease in the sinuses. I will write a prescription of antibiotics, decongestants and steroid & saline nasal sprays.
Only Zyrtec and Omeprazole will not help.

Till you see a doctor you can take Steam inhalations - that can help you.

Hope this helps.
get well soon,
Regards

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Brief Answer:
Yes start antibiotics

Detailed Answer:
Hello,
Yes of course you should take antibiotics and start them early.The infection in lymph nodes will go by antibiotics only.Take decongestants also.
You need to be investigated do not take steroid shot like this later.
You need to start nasal sprays for local action of steroids and the whole body doesnot need to be exposed to steroids.
Regards

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