That has the wrong profile and operculum shape to be a smallmouth.
I also can't tell from the pictures but it is either a rockbass (Ambloplites rupestris) to 17", not uncommon, (pic by N. Burkehead),
or it is a Roanoke bass (Ambloplites cavifrons) to 14", not common in NC but there are isolated populations where they are the most common larger fish in the area. (pic also from N. Burkehead).They do not have scales on their cheeks but rockbass do.
here is also a comparison shot of a smallmouth (Micropterus dolomieu) by Scarola. Note how much lnger through the body it is.
Top is the rock, middle roanoke, bottom smallmouth.
Both the Ambloplites are more tolerant of warm water and stiller water than the smallmouth. Both can be aggressive and often eat smaller fish.
Whichever you got, great catch!
It's certainly not a smallmouth bass.
It might be warmouth (based on the location that you found it).
I can't see the anal spines (which would confirm a Rock or Roanoke bass Ambloplites cavifrons)
Warmouth should have about 3 anal spines and all Ambloplites should have about double that.
JP. That doesn't look like a smally to me, but maybe its just the camera angle. Even though you are in NC, I would still think that they prefer coldwater. You might have caught them in the shallows, but they like to hang deep as well, rocky bottoms and drop offs are usually places where you might find them. 300gal would probably be sufficient to house him and more. Do you have other coldwater fish as well?