My doc put me on the advair inhaler. after using for a few days im stuffy and at night i feel like i've eat cotton. is this a side affect to this?

No and perhaps: Asthma inhalers should not lead to nasal congestion at night. (allergies certainly can.) inhalers can trigger cough and the propellant in the inhaler can taste funny and feel like a coating within the mouth, cause hoarseness etc especially if a person doesn't rinse and spit after using the inhaler. Using a holding chamber may decrease mouth side effects.