(Photo Credit: Michael Rozman/ Warner Bros.)

Fergie is known for being "up in the gym just working on my fitness" and three months after giving birth, it shows.

"I'm trying, I'm slowly getting back into it," she told Ellen DeGeneres after the talk show host commented on how good the new mom looks.

"I'm doing some belly dancing yoga," the singer, 38, said on an episode of Ellen's show that airs today. "I'm not going to show you right now, a couple more months for that."

Read: Fergie and Josh Duhamel Welcome a Son

Fergie added that even after years of performing with the Black Eyed Peas, she is taking it slowly as she starts to get back in shape and drop the baby weight.

"I just don't want to get hurt and all of that, so I'm taking it step by step," she said.

The "Fergalicious" singer, who gave birth to son Axl Jack in August, also dished on how she came up with her boy's name.

Related: Fergie Flaunts Post-Baby Body in Skinny Jeans

"I had this dream and I was in the audience at this festival. It was outdoors and it was all grimy and nobody knew who I was, I was just one of the fans. It was like the old days," she said. "On stage singing was Jim Morrison and then came Bob Marley and then Axl Rose, I mean I was in heaven."

She continued, "Then all of the sudden, boom, boom, and I wake up," she described the first time her son kicked her.

"It was like he was feeling the music with me," she added.

So, Fergie woke up husband Josh Duhamel and told him about the kick.

"I told the story and he was like, 'Morrison? Marley? No. Axl Jack. That's it!' It just had this ring to it. It was very strong," she said. Jack had already been decided as the middle name as tribute to Fergie's late uncle.