Hernandez has already scored 19 goals for Leverkusen this campaign, after leaving Old Trafford for £7.3million this summer.
The 27-year-old was often looked at as a bit-part player by United boss Louis van Gaal, but is relishing the opportunity to play a more vital role in Germany.
"What I was missing in the last two or three years, it was like I was playing sometimes and then returning to the bench," Hernandez said.
"But now that I am playing most of the game or almost all of my games here in my club, that's what I need.
"Because people sometimes think the confidence is with goals, but I don't think like that.
"I think confidence is to play day-by-day, to get rhythm."