spinach at 5 months

my pedia gave me the green light to give solids on her fourth month and so i did.. i asked my pedia what to give her and not my pedia advised me there’s no right or wrong on feeding your infant just as long as you give them 3 days to see if it will cause anything.. on her fifth i gave her pureed spinach and now i am reading that spinach should be introduced between 10-12 months... i was this bad?!