The Spaniard joined the Swans for £2 million in the summer from La Liga outfit Rayo Vallecano, for whom he netted 17 goals last season.
And Michu expressed his delight at securing a positive result in his first competitive game, but expressed determination to build on that success as the season progresess.
"My debut in the Premier League was incredible," he told Sky Sports.
"I never believed I would score two goals in a big victory for Swansea. I am very happy and looking forward to my first home match.
"It's not easy to score goals in England and to get two in 50 minutes was sensational. This is the way I dreamt it would be in this adventure.
"I just want to stay focused from match to match now. It will be hard to score two goals in every game but I promise the fans I will give my best in every game.
"The coach congratulated us after the 5-0 win and it was a dream start to the season."
The 26-year-old also insisted he will have no problem adapting to the physical style of the Premier League as he feels that is one of the main strengths of his game."The English style is different to Spain due to the importance on physicality in England," he added.
"But that does not bother me because I am used to being in combat with opposition defenders because that is my game."
Michu went on to say his side fully deserved their win over the Rs but highlighted his opener as crucial to the victory, especially away from home.
"Swansea were totally superior. Scoring early proved to be decisive because to win matches on your travels is never easy," he continued.