Nope! There were no other denominations in 325 AD. Well, denominations you could be part of and not be killed in any civilized part of the world. During that period of Christianity, there was no such thing as confession. Your sins were forgiven ONCE at Baptism, and after that you had to be on your best behavior. Hence why the likes of Constantine I of the eastern Roman Empire were baptized on their deathbed. That is what that line refers to, not what you're referring to, which is a post-Reformation spin on the Creed. Confession came later. Much later, and a retrofit happened.