you don't have to be pro to take good photos.
I'm not a pro...I certainly take tons of crappy shots.
With the dog photo, do you remember what focal length you used? 35mm? If it was any less i will be gob-smacked as there is no perspective distortion that i can see
The 16-35 is pretty damn distortion free....and this was with the D60 (i.e. the source is 6 megapixels). That was at 35mm though.