Does the Trinity really reflect the existence of our Father (GODHEAD). I have come to view Jesus as our big brother, who is perfect and never as part of the ALMIGHTY, but a creation of Him. Could I be wrong?
The question is, what do you mean by the Trinity? There are various differing concepts among the various Christian sects. The term, Trinity, obviously relates to the Father, the Son and the Holy Ghost. The problem arises from the concepts men have of the nature of the three members of the Godhead.
The belief of The Church of Jesus Christ of Latter-day Saints, for instance, is that the Trinity comprises three separate and distinct individuals, one in purpose, but distinct in person. God the Father and His Son Jesus Christ are perfect men, with physical immortal bodies of flesh and bone, and of finite dimension.
God is omniscient in that He has all knowledge. As recorded in the Book of Mormon in 2 Nephi 9:20—
O how great the holiness of our God! For he knoweth all things, and there is not anything save he knows it.
He is omnipotent, as is reflected in the D&C 1:38—
What I the Lord have spoken, I have spoken, and I excuse not myself; and though the heavens and the earth pass away, my word shall not pass away, but shall all be fulfilled, whether by mine own voice or by the voice of my servants, it is the same.
He is omnipresent by means of the presence of His Spirit and influence, but being corporeal in form His person of finite dimension is localized in space—
And the light which shineth, which giveth you light, is through him who enlighteneth your eyes, which is the same light that quickeneth your understandings;
Which light proceedeth forth from the presence of God to fill the immensity of space–
The light which is in all things, which giveth life to all things, which is the law by which all things are governed, even the power of God who sitteth upon his throne, who is in the bosom of eternity, who is in the midst of all things (D&C 88:11-13).
The Holy Ghost is also a person, but is a personage of spirit, not having a physical body, as other spirits acquire by being born into mortality. Thus, being a spirit, the Holy Spirit may enter into the bodies of mortals to testify of God the Father and His Son Jesus Christ, and to testify of all truth.
It is true, as you say, that Jesus is our big brother, in that He was the first born Son of God in the spirit world, and the only begotten Son of God in the flesh. Together with the Father and the Holy Ghost they form the trinity of the Godhead, each being a God. In fact, Jesus Christ is actually the God of the Old Testament, known to the prophets of those times by the name of Jehovah.