Is this Infringment of privacy?

Amanda
So my son is in Kindergarten and we have gotten him extra help as he is struggling so he is in special education and gets a lot of one on one time. 
Today I received an email from the secretary at his school with ALL the parents email address included with an attached PDF file for a survey for children in that school with disabilities/special education to fill out so now I and the other parents know who's kids are in special ed and have disabilities and the parents names as well as the email address are basically first and last name as mine is too. 
My husband went in to the school and was irate as she disclosed personal information and now we have taken it to the board of education. 
Later this afternoon I received another email from the same security stating it was an error and to delete prior email with undisclosed information. 
Are we as parents in the wrong for being upset? Should the secretary be reprimanded?