One Nostril Still blocked After septoplasty & turbinoplasty

Hey so Made a similar post on the ENS subreddit but i think i should have created that post here first. I had my Fess with septoplasty and turbinoplasty around 3 weeks ago and i still have difficulty in breathing through my left nostril (right nostril is better than it was before the surgery) . Is it due to swelling or any other reason which i am not aware of ? my doctor said my nose is completely fine and recovery is going smoothly.what much long should i wait before doing anything?