Well as your describe,it's Sinusitis with Eustachian tube blockage.
You should take OTC Motrin.
Also do steam inhalation and saline gargles.
You should do nasal saline spray and Otrivin nasal decongestant.
Continue Mucinex DM.
Also use a humidifier in your room.
And elevate your head while sleeping.
Try Valsalva manoeuvre
-Take a breath in. Then, try to breathe out gently with your mouth closed and pinching your nose. In this way, no air is blown out but you are gently pushing air into the Eustachian tube. If you do this you may feel your ears go 'pop' as air is forced into the middle ear.
If your symptoms'll not improve in next few days then see an ENT specialist for a clinical examination for further evaluation and management.
Hope this helps.
Use reply to let me know if you have further queries.
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