Don't smile at me Mommy

My small child is learning to inline skate. He puts on his skates and starts to chug around the basketball court feet furiously moving back and forth. I'm a little surprised that he gets anywhere this way but there is definetly forward motion. "March a little, kiddo" I call out. "It is more of a step than back and forth." He is ignoring me. Finally he finds the new rhythm. March, march, march, roll. March, march, march, roll. "That's it!" I say. I watch him smiling. He mumbles, "No smilin'." I'm not sure I heard him properly. I grin as he rolls again. "Don't smile at me, Mommy," he says in a frustrated tone. I thought these teenage moments would wait until nine or ten. It seems we have them early.