Strange Permanent White Patch Developed on my Nostril After Open Rhinoplasty? (photo)

If I am interpreting the photograph correctly it looks as though there is asymmetry of the insertions of the medial footplates of the lower lateral cartilage. These can be delivered in fixed with local anesthesia.

That looks like your cartilage footplate, it is a bit more prominent on one side as compared to the other.  The white colour is that of cartilage seen under moderately thin skin.  An attempt at revising it can likely be done under local freezing.  Talk to your surgeon, revisions should wait until one year after the original operation.

We just can't diagnose from a photo, though your surgeon should have the 'befores' to compare and see if the spot was indeed there. Revision after rhinoplasty is possible if the shortcoming is clear and the repair plan is sound.

The white patch is looks like it is secondary to pressure from the underlying tip cartilage. A physical examination would be necessary to confirm this impression. If you are considering a revision because  you're "not happy at all with the results of the surgery" this can be corrected at that time.