My son is having a problem with one of his teachers?

my son who is 10 has from last year had aproblem with one of the teachers at school she only takes him once or twice a week for pe and drama last week he came home in tears because she called him a young lady in front of all his friends this week in tears again had called him a cabbage whatever that was suppose to meen i went and seen the headmaster yesterday about her and he said he would speak to her on tuesday as the school is closed on holiday until then i have heard from other mothers that she has been doing and saying things to some of there kids as well so its not just mine even the janitor has told me she is not a nice person and is not nice to the kids,i just wondered what other people think about this or is it just me being overprotective of my son,i know he will have a laugh and a joke with his friends but he is not a bad or cheeky boy hes just a boy and boys will be boys and that was also the words of the headmaster,what do you think.