Baby fat questions !

My baby just made 8months the 16th of this month. He was born at 7 pounds 8ounces. He was very thin until about 4 months he’s gotten extremely chunky. He’s 28 pounds and he’s 8months. He’s barely interested in solids, he rather have his bottle but I still try to aim for 2 times a day with solids. He sits un assisted, and is trying to crawl. He’s meeting every milestone, and is super active. Everybody thinks I over feed him but I don’t. I’m kindve worried about his weight. Why is he so chunky did I do anything wrong ?