I have been sick for 4 days with allergic conjunctivitis and sinus infection from tree and grass pollen, how many days can this last?

Allergy VS infection: Great question! it depends if allergy or infection. Allergy symptoms usually last on and off for weeks or months, throughout the allergy season. A sinus infection often runs its course after a few weeks, although it can take an antibiotic to get rid of it. You can check a pollen count website to see if your symptoms are worst on high pollen days. See a doctor if symptoms last more than 2 weeks.

Treat infec/allergy: If you have thick eye drainage as well as thick nasal drainage, these symptoms may be related to an infection. Typically, the drainage is clear if due from an allergic reaction. The two conditions may be related in that the allergic reaction causes inflammation which can decrease local defenses to infection. Both can occur, and I would suggest avoiding pollens, closing windows, & staying indoors.

End of pollen season: If you are having symptoms now, your allergy may to to ragweed and molds and not tree and grass pollen. There are OTC antihistamine eye drop and nasal steroid you can try. But you may need to consult an allergist if things don't improve. Your symptoms will likely linger until the first frost in your state.