The History of Covenant Theology by R. Scott Clark says

Until recently, it was widely held that covenant theology was created in the middle of the seventeenth century by theologians such as Johannes Cocceius (1609–1669). In fact, covenant theology is nothing more or less than the theology of the Bible. It is also the theology of the Reformed confessions. In the history of theology, the elements of what we know as covenant theology; the covenant of redemption before time between the persons of the Trinity, the covenant of works with Adam, and the covenant of grace after the fall; have existed since the early church.

Indeed, Reformed readers who turn to the early church fathers (c. 100–500 AD) might be surprised to see how frequently they used language and thought patterns that we find very familiar. The covenant theology of the fathers stressed the unity of the covenant of grace, the superiority of the new covenant over the old (Mosaic) covenant, and that, because Jesus is the true seed of Abraham, all Christians, whether Jewish or Gentile, are Abraham’s children. They also stressed the moral obligations of membership in the covenant of grace.

The covenant theology of the medieval church (c. 500–1500 ad) was related to that of the early fathers but distinct in certain ways. In response to the criticism that Christianity gave rise to immorality, the early church tended to speak about the history of redemption as the story of two laws, the old (Moses) and the new (Christ). They tended to speak of grace as the power to keep the law in order to be justified.

According to Ursinus, in his obedience for the elect, Christ fulfilled the covenant of works and bore their punishment. On this basis God made a covenant of grace with sinners. The message of the covenant of grace is the Gospel of undeserved favor for sinners.

This was the focus of Caspar Olevianus influential book, On the Substance of the Covenant of Grace Between God and the Elect (1585). He taught that the covenant of grace can be considered in a broader and narrower sense. In the narrower sense, the covenant can be said to have been made only with the elect. It is the elect who are united to Christ by grace alone, through faith alone, in Christ alone, who receive the benefits of the covenant, strictly speaking.

First off, great questions. As with most of Covenant Theology the roots go back to Calvin, who deals with them at length in Institutes (II.X-XI) But, while Calvin does speak of a distinction for the Adamic covenant, it is not until 1569 that a Covenant of creation is mentioned and 1585 that the term "Covenant of Works" is first used by Westminster Divine, Douglas Fenner. As with most of theology, the idea of metacovenants developed gradually - and so to speak of concurrent development depends on the window of time you want to allow to the process. But if your question is, simpliciter, were they developed by the same person or in the same work, the answer is no. Your third question is also a matter of opinion. Some would say Yes, and some would say No. Some of the Yes's would be "hard" yes's, and some soft - and the same would be true with the No's. The nuances of how people answer that question is an essay in and of itself. For me, personally, I am probably a soft no. We have learned a great deal about the particulars of covenants from 20th century archaeological finds, especially the Dead Sea Scrolls - and those have had consequences for the way Covenant Theologians approach the very idea of covenants, not to mention the heft of the covenant of Grace. Furthermore, language is such a vital part of epistemology that for me, it is nigh on impossible to say that there are not substantial differences in the understanding of the doctrine since its inception to today - based on the discrepancies of linguistics alone.