The early christians did believe, that Jesus is the devine son of God, that He died for our sins, that his tomb was empty, that he appeared to 500 people and went to heaven. Read Pauls letters from 50 A.D like philipians.
"Have this attitude in yourselves which was also in Christ Jesus, who, although He existed in the form of God, did not regard equality with God a thing to be grasped, but emptied Himself, taking the form of a bond-servant, and being made in the likeness of men. Being found in appearance as a man, He humbled Himself by becoming obedient to the point of death, even death on a cross. For this reason also, God highly exalted Him, and bestowed on Him the name which is above every name, so that at the name of Jesus every knee will bow, of those who are in heaven and on earth and under the earth, and that every tongue will confess that Jesus Christ is Lord, to the glory of God the Father."
Sects were built on dogmatic beliefs like Trinity or who is the antichrist. It happens with every religion. Even islam is devided into sects because of dogmatic beliefs like succession of Muhammad, hadiths or interpretation of Quran. There is even a sects that believes that Muhammad is devine, And Ali God. And I don't think that either sect of islam can be right, because they disobey one of Allahs laws to not split into sects. Islam is doomed. Islam is devided exactly like christianity, and I guess your sects will come into paradies, and others won't. I bet you think, that your sect is the only right one, no? Guess what, almost every sect thinks that.