"I felt very inadequate; I felt like I'd made the worst decision of my life," she told her interviewer Lisa Robinson. "Eventually I just said, I'm going to give myself an afternoon a week, just to do whatever the f*** I want without my baby."
Adele admitted that taking regular time out for herself often leaves her feeling guilty, but she believes it's the best way to get through the challenges of being a new mother to Angelo, who has an older sister from Simon's previous marriage.
Her revelations stand in stark contrast to her interview with on NBC's Today show late last year, when she told host Matt Lauer she'd "never been happier".
"And I've never been healthier. So I'm good," she added, while promoting the chart-topping follow-up to her previous smash hit album 21.
She even commented that being happy wasn't necessarily the ideal situation for an artist, explaining it made it "impossible" to pen songs for her album because, "to be honest, I wasn't sad".
The singer took four years off between albums to focus on her son Angelo, now four, with partner, 42.
Her little boy has, she said, made her a more emotional person "in every single way possible".