"Doing that dance, I was just living in the moment. Then all of the sudden, halfway through, I got the worst feeling in my neck. I cracked, popped, snapped something. Couldn't feel anything from my hip to my head," she told ET. "I was like, 'That is not ruining this moment.'"
"I couldn't see. I literally couldn't do anything until I up got to pick [Johnson] up at the next lift," she added. "I was like, 'Get it together. Four eights. Pull it off.'"
Pushing through both that dance and her Rumba to Jackson's "That's the Way Love Goes," left Siwa feeling "pumped up."
"We had the best night. We killed our dance, nailed all our lifts, hit all our tricks, killed it," she said. "Then we came out and did rumba. Killed it. Got the two bonus points, murdered our night."
"Obviously, you're kinda close with Val. Not like married or anything, but like married," Siwa quipped to Johnson. "And Olivia is so awesome. [She] had become one of my best friends here. Saying goodbye to them tonight was brutal."
"It sucks," Johnson agreed. "I am devastated for [Chmerkovskiy and Jade], because I know the hard work they've put into this season. I honestly thought they were going straight to the finals, so I'm a little bit confused."
"I know how much Val loved this season," she added of her husband. "This was the first time he got to dance in a while, and I think Olivia was the perfect partner for him... The four of us had this team gang thing together and I'm just sad. It just sucks. It's the worst."
Although saying goodbye to her fellow competitors was tough, Siwa is grateful that she's on the show and that she can continue to be herself publicly. The singer came out in January.
"I'm so happy. I think every little gay human knows when they're a kid, and it's something you hide inside until you are ready to share with the world," Siwa told ET. "Finally sharing it with the world, and having the world accept me and celebrate me, just felt so nice."
"I also felt like it gave encouragement to so many other people, which is what I love and appreciate the most," she continued. "I've been in the public eye for over half my life now, and so I know that I have a voice, and I know that I have a platform, and so I try to share encouragement with the world and show them that you can be who you are."
Dancing With the Stars airs Mondays at 8 p.m. ET/PT on ABC.