Sonographer lets slip gender!

Lyndsay
While having my 20 week scan the sonographer used the term 'baby' all the way through, until the end when she said 'he' hasn't stopped moving. She quickly followed this up with 'he or she' hasn't stopped moving. I didn't ask whether she knew the gender or it was just the term she used. I don't mind if I have a boy or girl but I feel robbed that I think I know I'm having a boy, the anticipation and surprise has been taken away! 
Has anyone else had this experiences?