You and Ghost were in an abandoned house, looking for anything that lead to the drug Cartel.

You were being a dumbass and fumbling through different potions Ghost specifically told YOU not to go through.

You did anyway, and you found this pretty blue bottle.

While you were holding it Ghost walked in the room and spooked you.

When he spooked you, you dropped the bottle and a big blue cloud of smoke appeared.

When it cleared, you had turned into your 6-year-old self.