3 and half month

Question
Max (Male) got pooty trained very early, ever since he was 2 months old- he would only go out of the house to the back yard to poop and pee... i found him ( humping a toy boxer)... is int he too young to be doing that??  ( is he mentally thinking that he's old - i am curious coz he started behaving matured at a very young age-- he also gets bugged with me when i say "no" everytime he tired to pull my any clothes on the floor- he barks at me..( can i slap him (gently) on his cheek?  - (he;s only allowed to bite the chew bones)

Answer
Hello,

I'm sorry but because of the many grammatical errors in your post, I'm unable to understand all of your questions.

To answer what I do understand:

Humping is not always a sexual behavior.  In dogs, males especially, it can be a dominance display.  He may very well be 'humping' his toy out of excited play and/or dominance and not receiving any sexual gratification from it.

No, it is not ok to slap your dog...gently or otherwise.  If you want him to stop biting, there are more humane approaches available.