Hiya,
Yeah my little boy did it that early to, I had him neutered but he still about twice a week and only ever after his supper at 5.30pm

has a little 5 min hump of his favorite soft toy. We are very bad and actually call the toy "his girlfriend" if I ask him where his girlfriend is he goes and gets her. He kisses and licks her a lot to.
I didnt know this was a dominance thing which makes sense because "DOMINANCE" is Jakes middle name I have had to to a lot of work on getting him to know I am the leader of the pack and he still needs reminding often!
It doesnt bother us him doing it but maybe I should be stopping him??????
Ruthx