Kelly Clarkson has realised it was "kinda stupid" of her to host the 2019 Billboard Music Awards while battling appendicitis.

The Since U Been Gone hitmaker returned to Las Vegas to emcee the annual prizegiving on 1 May (19), and even performed twice for fans during the three-hour ceremony, before dashing off to undergo emergency surgery.

Kelly assured fans she was "feeling awesome" in a Twitter post hours after the operation news hit headlines, but by Sunday (05May19), she admitted the recovery period "super duper sucks" because she isn't a great patient.

The singer returned to the spotlight on Monday as she resumed her role as a coach on a live episode of U.S. talent show The Voice, and in a chat with U.S. news show Entertainment Tonight, she played down all the praise she has received for pushing through her condition to complete her Billboard Music Awards gig as host.

"Here's the funny thing: everybody kept being like, 'Oh my God. You're superwoman!'" she shared. "Nobody knows meanwhile, I performed onstage, and have been performing, with one of my friends that's, like, fighting cancer..."

Kelly didn't name names, but continued, "It feels just silly, people saying like, 'Oh, I can't believe she did this.' And I'm like, I have friends that are going through much worse scenarios and doing it on the daily."

The pop star credits the adrenaline rush she experienced onstage with helping her play through the pain, but as soon as she wrapped up her duties as host, the extent of her condition really kicked in.

"I felt uncomfortable during the show, but it didn't really hit hard until the end of the show and my adrenaline just, like, left the building...," Kelly confessed, insisting she is doing much better now. "It's fine. Everything's good."

However, the mother-of-two recognises that performing with appendicitis was "kinda stupid," even though her doctor had signed off on her big gig hours earlier.

"I probably shouldn't have (pressed on with the show), but I did ask my doctor and we had things (preparations) going on in case it ruptured or whatever...," she explained. "It wasn't just like, 'I can do it!' Like, I wasn't an idiot about it. But I probably wouldn't do it again."