Also take into consideration your big move, and the dog's instinctual need for routine and a schedule of things to do. Walking a dog isn't so important as to release Tito's energy in a way that makes him feel a part of your routine and schedule, helping him feel secure and accomplished while
exercising his body. Since there's been a lot of changes in his world, he's reaching out to steady himself and give himself confidence in unhealthy and manipulative ways.
It doesn't sound to me like he's too far along, he's just testing his boundaries. All dogs will stumble into a bad quirk accidentally, but it's about recognizing that random quirk when it starts happening (barking for fun, a rough play bite) and giving a clear and absolute alternative that you (the person Tito trusts) are comfortable with before
the habit gets too cemented.
Alternatives include (but are in no way limited to: )
-redirection ("Here, chew this instead!" or "Here, eat this instead!")
-distancing Tito from the negative situation (hooking him up to a leash near his food and water) until he calms
-removing Tito altogether from the negative situation until he calms (crate or playpen. A different room may heighten anxiety)
Set Tito up for success! If you know that he runs to the door and can't stay, put him on a leash when people come over and reward him if he's calm. If you know Tito is getting too rowdy while playing, stop playing the game that was riling him up and play another game. If he isn't understanding what you're asking, do some research and switch your methods up a bit. All dogs are different!
Most importantly, teach Tito about his world! You'd be so surprised just how fast these little dogs learn if you just talk to them about things. My chihuahua picked up what "water" was just by me telling her "water" every time she drank. If you haven't taught him how to "Sit" perfectly
then that's the best place to start. It's your jumping off point. That way, when Tito doesn't understand what you're asking, you both can default to sit without frustration or obligation and start the lesson over, or end on a good note.
Taking him outside twice a day in a structured environment will also help drain his energy and stimulate his eager little mind. Just sounds like some "teenage angst"
I wish you & Tito luck! He may just grow out of the whole thing entirely! Always remember, it's important for you to be comfortable with all the methods you use. Never use a training method you're unsure about or don't understand.
Please keep us updated!