Paris Jackson -- My Tat Confirms ... I Was My Dad's Queen (PHOTO)

Paris Jackson gifted herself on her 18th birthday with some fresh ink honoring her beloved dad Michael.

Paris emblazoned "Queen of My Heart" on her forearm, courtesy of tattoo artist Justin Lewis. He copied MJ's own words, in his own handwriting in a letter to Paris when she was just a little kid.

Paris explained it this way ... "To everyone else he was the King of Pop. To me, well, he was the king of my heart."

1:40 PM PT -- Paris' brother, Prince Jackson, also got some ink. It looks like he went with an Anubis -- the Egyptian god of the underworld.