According to the law, it is. (Even without castle doctrine a random stranger trying to gain entry into your house is usually grounds for self defense).

If the kid didn’t open the door, then I agree with you. But even the kid admitted to at least grabbing the handle of the door. I’d personally never do that at stranger’s or even an acquaintance’s house.

From a moral standpoint, please don’t try to walk into stranger’s houses uninvited.