'American Idol' Alum Jax Reveals She Was Diagnosed With Thyroid Cancer

Getty Images

American Idol alum Jax showed her fighting spirit when she clawed her way to the No. 3 spot on season 14 of the singing competition, but the fight of her life came after the show.

In an interview with My Central Jersey, the 20-year-old singer revealed that she was diagnosed with thyroid cancer in April shortly after performing at a concert.

WATCH: 'American Idol' Contestant Jax Wore #TheDress!

"It was very unexpected," Jax said. "When you're 20 years old, you have this Superman entitlement mentality. Like you're indestructible. Thank God I have people in my life that were there to help me deal with this when my reality finally clicked for me. I'm a tough guy, but I don't think I have ever experienced anything scarier."

According to Jax, she felt a lump in her throat while grocery shopping and got herself checked out at an urgent care facility. After undergoing tests, it was revealed that she had 18 tumors on her thyroid, 12 of which were cancerous.

Jax said that she felt "depressed" and was in a "really dark place" in the days leading up to her diagnosis.

"People don't realize how important the thyroid is. It's more important that the actual brain," Jax said. "It was messing me up emotionally, putting me in a strange place."

After surgery, all of the tumors were successfully removed and Jax is currently undergoing iodine treatments.

PHOTOS: Complete List of American Idol Winners

"I'm radioactive right now," she said.

In the midst of her recovery, Jax is not letting the setback slow her down. She's planning to participate in the 2016 TCS NYC Marathon on Nov. 6 to help raise funds for Tuesday's Children, an organization dedicated to helping youth and families affected by terrorism.

"Sometimes I think the universe is yelling at me to slow down and I just blatantly ignore it," she wrote in an Instagram post on Monday. "However, my health has to come first. I understand that now."