3 yr old

So my three-year-old who was also my first child kind of just discovered his pee pee cuz he been potty trained recently so I would think his dad would understand him touch it alot and all that type of stuff I thought that was normal but his dad freaks out to the point it makes me feel like should I be concerned to me he hasn't done anything that would warrant a doctor's appointment. When he's waiting for new underwear or waiting for a pull up he flicks it a lot when I first ge him out of the bathtub he likes to be naked he'll run through the hallway and shake his pee pee once in a while but it's more like he's shaking his whole body not just his Pee pee. My sister-in-law said they went to the aquarium or something and he was putting his pee pee up against the glass I mean he was fully clothed so does any of this sound concerning.