That's a cool story bro (not trolling) haha when I got gold I didn't know the difference between shiny and not shiny, I realized I got a shiny houndour (favorite pkmn) so it was sorta the same for both of us xD
It was a Shiny Chansey, from the safari zone in FR/LG. this wasn't on a rom, it was real. That was the first Chansey i ever saw, so I thought it was normal, and somehow I caught it. After my firend told me Chansey were not supposed to be green, and they were rare, I searched up about shiny Pokemon, and that it. Traded it to Diamond, then to HG, then to my White.