Airline Carry On Rules

Hi everyone. I’m bringing my dog (shih tzu) upon the craft with me. But we wish to know the expect procedures so we do not get any surprises at the airport. we will be travelling from Canada to the US around American Airlines. I’ve checked with the airline about the prices and everything.. But what we wish to know is when we check in with my bags and all, do they take my dog from me? Will we be usually removing him behind upon the plane? Or do we lift him with me via the complete time (security check and all) until we get upon the plane? So he’s a tiny dog, that will be means to fit underneath the chair in front of me. But what if he needs to eat? The airline doesnt concede him to eat? (They contend my dog needs to be inside the conduit at all times during the flight.) And what if he pees? we need to purify him!

I’d unequivocally conclude answers . . . generally from people who’ve already trafficked with their pups upon AA. Thanks a lot in advance!