My windows are closed & locked and the ac is on

The shopping cart nazi drove me to use my air conditioning. I pushed my shopping cart to the side instead of putting it in an appropriate spot at the grocery store today, so some guy followed me home in his black suv... Informed me I'd left my cart in the wrong spot, and asked if I wanted to go back and put it away. I said"hrmm. Nope" and he said "Okay, well, I'll be back later" I went into the house and locked the door - and heard a thud from outside. I went out later and found like a 2 inch round nut on the grass next to the house - so I guess he threw it at the house.

I'm assuming noone's stupid enough to actually come back to escalate a shopping cart issue, but then I wouldn't have thought anyone would have followed me home to throw metal things at my house - so I decided to lock up more than usual.