Seeing her son whisked to the neonatal intensive care unit right after his birth was hard enough, butDanielle Fishelsoon learned that mom guilt sets in pretty quickly too.

In this week’s PEOPLE, on newsstands Friday, theBoy Meets WorldandGirl Meets Worldalum recalls the harrowing experience following her and husbandJensen Karp‘s sonAdler Lawrence‘s June 24 birth one month early and subsequent three-week stay in the NICU after doctors noticed fluid retained in his lungs.

“This milk that I’m producing that’s supposed to keep him alive and is supposed to be the healthiest thing for him is the thing that’s keeping him in the hospital,” the actress says of her internal thoughts. “I just felt like it was somehow my fault. Even though I knew that wasn’t really rational, it’s hard.”

Danielle Fishel and son Adler.Justin Coit

Danielle FIshel

Adler Lawrence Karp.Justin Coit

Danielle Fishel

For now, it’s one step at a time for the first-time new mom — and she’s keeping her expectations realistic.

“I don’t anticipate [Adler] ever latching because he’s never been on my breast before, so it may be possible that he’s never able toactually breastfeed that way, butI have plenty of milk stored and I can always feed him from a bottle,” she tells PEOPLE, adding proudly, “He’s a pro with the bottle now.”

While Fishel “can’t speak for” her producer husband Karp, 39, she insists that “mom guilt does not waste anytime kicking in” after a child is born, admitting she experienced it “instantly.”

“Every second that you are awake doing anything,you feel guilty that you aren’t at home,” she says. And on the flip side of that, “Every second that you’re at home, you feel like you’re missing out on the other things that you’re supposed to be doing.”

Danielle Fishel and Jensen Karp with son Adler.Justin Coit

Danielle FIshel

Justin Coit

Danielle FIshel

Fishel and Karp took their son home fromChildren’s Hospital Los Angeleson July 15, after he was monitored for three weeks. (His lungs eventually healed on their own.)

But it’s worth it,considering Adler’s cuteness andsunny disposition. “He’s giving us lots of smiles and he’s very strong. He’s holding his neck up, he’s looking around,” Fishel shares. “When he is awake and alert, he makes very intense eye contact. He’s very curious. We can’t wait to hear what his voice sounds like. We can’t wait to know what his final eye color is going to be.”

For more from Danielle Fishel, pick up the latest issue ofPEOPLE, on newsstands Friday.

source: people.com