Donor area over harvested? (Photo)

Over harvesting from FUE can be an issue and cause the patchy appearance.  It may also be due to shock hair loss.

As of now, it does look like that there is a difference in the residual density of hair on both the sides but you should wait for three to four months before knowing what will be the actual look of both the areas. 

It is not the absolure number of grafts that cause over-harvesting but the relative number of grafts as measured against your oriiginal donor density that dictates it. Your doctor should have measured your origianl donor density and anticipated this problem. Best treated with scallp microigmentation, see below