The alternate blockage of the nose that you describe is very normal, it happens with all of us. This is called the Circadian rhythm of breathing of the nose, our noses autamitically get impeded on one side and open on the other alternately. This is what you are experiencing, you shold not stress yourself over this.
If the ENT has cleared you, it means that you do not have major illnesses like DNS or sinusisitis. You may be having some slight congestion, in addition to the nasal sprays you can try the following:
Decongestants - Sudafed 120 mg once daily(OTC) for 10 days.
Another important home treatment is Menthol steam inhalation - add Menthol salts (available OTC) to a bowl of steaming water and inhale the steam two - three times daily - this will relieve the congestion.
This should be sufficient to keep your nose clear.
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