Prophylactic means something to prevent disease.
it means...that you mean what you mean:)
1.not nice 2.rude and disrespectful to other people 3.opposite of nice 4.cruel 5.harsh through words or actions
It could mean that you are nervous that you will disappoint someone you respect or care about.
it means they would not care if someone was as mean to you as mean as they were to you. sometimes it means they do and its just that they are too insecure to tell the truth and use childish anticks...