Is it normal for a boy to smell your feet

The other day my buddy, who is 13 year old family friend, got hurt. I was sitting down and he was laying by my feet and saying his finger got bent back. I noticed his face was really close to my foot and he started breathing heavily. I didn't realize it at first but then thought he's smelling my feet. He then moved towards my left. I was consoling him because I thought he was hurt. He then said he was joking and wasn't hurt. Then later on we were playing football and he kept trying to pull my shorts down. He also kept trying to tackle me. He punches me in the balls a few times. He holds back so he doesn't hurt me cause he can hit hard. I know he likes to hang out with me but he's been more physical lately. He's done this other stuff before but not smell my feet. Is this normal?