Well, no one will whip you for reading a Protestant translated Bible but there are certain things you should look out for before depending on just any kind of translation for guidance.
For example, some translations leave out the 7 Deuterocanonical books. That means anyone who will be making use of such translation will be missing out on a lot of things being that he will not be reading the complete 46 books of the Old Testament but only thirty-nine.
One who is not well grounded in biblical studies and the teachings of the Catholic Church will highly be at risk of being swayed by wrong teachings and false doctrines because it is only a matter of time before one knowingly or unknowingly starts to believe doctrines that are opposing to the Catholic ones.
This is why there is a list of translations approved by the Church for Catholics to use. For example, the United States Conference of Catholic Bishops since 1983 approved a list of translations like Books of the New Testament Alba House, Contemporary English Version and others. It will do you a great good to rely only on translations approved by the Church.