The 33-year-old singer opens up in a new interview about how she balances it all, and has her own advice for working mothers.
"Ask for help. Accepting help is hard for me, but I'm learning," she tells the November issue of Redbook magazine. "Sometimes I feel guilty that this is my son's life: We live on a bus and we’re in a hotel room and sometimes we're in the middle of nowhere and it's not so great. It's not all glamorous."
"We have a nanny who helps out, especially when we're on the road," she adds. "But I'd feel guilty asking someone to watch him at home while I run to the grocery store."
Underwood and Fisher welcomed Isaiah last February, and the American Idol champ couldn't be more overjoyed about her life as a mother.
"I definitely feel like it's changed me as a person. I'm happier," she says. "I'm in a better mood a lot of the time. He’ll be watching cartoons and I'll be watching him. I'm completely in love. I love it when he's sleepy and I get to hold him and smell him. He doesn't know I'm staring at him and being all googly-eyed!"
Underwood is definitely open to having more children with 36-year-old Fisher.
"If my husband were at the beginning of his career, I’m not sure we could handle it," she admits. "Since he’s kind of nearing the end and won't be traveling so much, we're like, 'We can figure it out for not that long.' You make it work."
"When I was pregnant, I thought, How am I going to go on the road? How am I going to keep doing my job?" she recalls. "I had to just give it to God and stop worrying about it. Sure enough, we figured it out."
Last month, Underwood hilariously shamed her dog Penny for stealing Isaiah's French toast. Watch the adorable moment below!