Breathing Problem After Turbinate Reduction and Septoplasty?

A septopplasty will not necessarily correct the external appearance of the nose. There may be many reasons for your persistent nasal obstruction incuding post operative swelling but I would bring this to the attention of your physician and you may need another CT scan to evaulate the cause of your symptoms

You are still very early after your surgery. In most cases, just correcting the deviated septum, which usually remains deviated anyway, will not affect the breathing that much unless it is really bent and obstructing the airway. Removing, not just injecting or cauterizing, the enlarged, obstructing turbinates should have a dramatic improvement in breathing.

What you are describing is not ideal.  You didn't mention if when the packing or splints were removed if you could breathe well.  If so, you might just be swollen right now.  If not, there might still be an anatomical obstruction present.  Another CT could help and certainly visit your doctor as frequently as necessary.