Does homeschool make you dumb??!!?

Okay so I have been home-schooled for like 3 years now and I feel like I've gotten dumber! Like seriously I was like one of the smartest people in my cl and now I'm just dumb and lazy! I don't have any discipline...I study when I want, where I want and however I want...& i'm a high schooler...so did homeschooling make me dumb or am I mentally sick in the head??!!