You scaled in object mode. Either select your model and press alt s and scale it back in edit mode, or spawn a new cube, select your model then hold shift and select the cube. Then press ctrl + j and delete the cube in edit mode.
MMk, about that whole cube procedure.... It worked the first time I tried it, no prob. Second time = FAIL. No clue why, did it exactly the same, just with a different model. Next model I did, YAY it worked again, no issues. However, I have 2 new models Im doing and when I hit ctrl J, the cube does change color and it fixes it. HOWEVER when I go to export the model, the materials all disappeared from the list (there were 4 now and now there are none) and the exporter crashes and fails when I try to export. This happened with 2 different models wtf?