Aly Michalka Is Pregnant! Singer Expecting First Baby with Husband Stephen Ringer (Exclusive)

Aly Michalka is pregnant!

PEOPLE can exclusively reveal the Aly & AJ musician and actress, 34, is expecting her first baby with filmmaker husband Stephen Ringer, to whom she's been married since 2015.

"It's been a really easy pregnancy, which I feel really lucky and blessed to have experienced," Michalka, who's due in May, tells PEOPLE.

The iZombie star found out she was pregnant in September — one day before she and sister AJ Michalka played a sold-out concert at the Greek Theater in Los Angeles in September.

"In another world I could have waited to take a test another day, but for whatever reason I was like, 'I'm past a week being late, and I should just take the test,' " she says. "And then it was just like, 'Oh my gosh. We play this huge show tonight, and now I'm holding in this huge secret.' "

Aly told Ringer, 39, immediately, but she waited until after the concert to clue others in — which was difficult, considering she usually tells AJ everything. "I didn't want it to take away from the special meaning of that night, and we already had so much on our minds that we were juggling," she says.

Days after the show, she took AJ out to dinner at Pace in L.A. to share the big news. "I was like, 'There was a special guest that was at the Greek that you didn't know was there,' and she was like, 'Who?'" explains Aly. "I was like, 'There's a baby,' and I touched my stomach, and then she was like, 'What?!' She was just really excited and overjoyed. From there, we told the rest of the family."

The pregnancy arrives nine years into Aly and Ringer's marriage. While they've always wanted a family, the pair wanted to wait until after she returned home from touring last year to begin planning.

"It was nice that it ended up happening quickly, but also I think that took us by surprise in a way where we were like, 'Oh, we thought that maybe this would take us eight, nine months to get pregnant or a year,' and it didn't," she says. "Recently, it's started to feel really real just because I'm now starting to show — and I took my belly ring out, which means that the stomach is really popping out."

So far, the pregnancy has been without abnormalities. Aly's found herself craving tacos and birria but nothing "crazy," and she's been seeking advice regarding what to buy and how to prepare from her mom Carrie as well as multiple friends who are also currently pregnant.

"It's been really smooth sailing so far, and I was lucky I didn't get any nausea at the beginning. I've just been just trekking away as usual," she says. "I have to drink a lot more water and eat a lot more protein than I've had to in the past, which has been a struggle for me. But I'm trying to do it daily and be on top of it."

When it comes to products, from pregnancy tests to belly oil, Aly's go-to brand has been Natalist, which she's currently partnering with. Before entering a working relationship with the company, she stumbled upon some items in a pharmacy and noticed many of its values align with hers.

"They're plastic neutral, which is really nice. Whatever plastic they're putting into their product, they're making sure that they're working with a company that extracts plastic from the ocean," says Aly. "It's actually a really cool brand that is the first of its kind out there for fertility stuff."

About three months out from her due date, the musician has been discussing baby names with Ringer, and they've picked out three possibilities for a boy and another three for a girl. "We want the name to feel unique, but I also don't want people to roll their eyes, like, 'This is such a celebrity kid name. This is so ridiculous.' So I'm like, let's just stick with a cool classic name, maybe something that sounds like an author or a writer or a musician," says Aly.

Despite "most everybody" they know asking about the baby's sex, the pair plans to wait until birth to find out. "We're not really the couple that would do a gender reveal anyways," she explains. "I don't think that, even if we knew the gender, everything would be blue or pink."

Looking forward, Aly's excited for the journey of parenthood with her husband. "I can see Stephen being a really great dad, obviously, which is a reason why I wanted to have kids with him. He'll be very tuned in to their feelings and emotions," she says, noting that one of her big focuses is to make sure their child has "a really good food palate — we cannot just do chicken fingers and plain hamburgers."

More seriously, Aly wants to make sure her baby learns to have a "thoughtful and kind" outlook toward others. "[We want to teach them] they do have some privilege, obviously, growing up in Los Angeles with two white parents. I think putting that as a topic to talk about with your kid early on is really important," she says, "because then they'll be empathetic toward all kinds of people in their future."

Her child will certainly gain a well-rounded worldview, as Aly plans to take them on the road once she and AJ resume touring. The sister duo is currently writing material for a new album to be released "ideally" next year if all goes to plan with the timeline of her pregnancy.

Among the topics to come up in the forthcoming album's lyrics, fans can expect to hear Aly muse on motherhood. "We wrote a song the other day that touches a little bit on that," she says.

For more from Aly Michalka, pick up the latest issue of PEOPLE, on newsstands everywhere Friday.