The 25-year-old scored two goals in the Italian champions' 4-1 away victory over Udinese in Serie A on Sunday.
"Am I a top player? I never thought of myself as one, to tell you the truth," he told Corriere dello Sport.
"I must learn to be more confident in front of goal."
Giovinco rejoined Juventus this summer following an impressive 2011-12 campaign for Parma.