Two completely separate placenta

When my son was born,  he was 4lbs 9oz. He had high respiratory,  low blood sugar and high red blood cell count.  My pregnancy went normal and everything was just fine.  I gave birth at term.  After his birth,  the doctor examined the placenta. He discovered that there were two completely separate placenta.  They weren't torn or ripped apart,  they were completely separated.  I asked my doctor what it ment,  and he said it possibly ment there was suppose to be twins,  but there was no second child and no real signs of a second child other than the separate placenta.  My son is Gemini,  and definitely shows signs of dual personality.  He's 25 years old now and I thought he would outgrow it,  but the duel personality still exists.  One personality is the male personality and he has somewhat of a female persona.  Not worried,  but curious if it were possible that he asorbed his twin from the start.  Just curious even after 25 years