Hello.
I understand your concern.
Severe headache,watering eyes,cough with expectoration is because of
acute sinusitis.
Heart burn can be because of gastro oesophageal reflux disease that worsen the throat related symptoms.
If I were your treating doctor,I recommend,
-Antibiotics like Augmentin thrice a day for 5-7 days(prescription drug)
Analgesics like
acetaminophen twice a day for 3-5 days.Avoid ibuproen/naproxen as it may worsen heart burn symptoms.
-Oral antihistaminics cetrizine once a day for 3-5 days.
-Steam inhalation thrice a day for relieving
nasal congestion.Nasal decongestant spray can be used for 3 days if congestion is not relieved by steam.
-PPIs like
omeprazole once a day for 1 month.Avoid alcohol,hot,spicy,fried food.
If symptoms have lasted for more than 3 days,visit to physician.
Hope this information helps,
Any further query is welcome.