Heather Rae El Moussa is navigating a difficult health issue.

The 36-year-old Selling Sunset alum was recently diagnosed with a common autoimmune disorder.

During an interview with Today, Heather Rae opened up about her symptoms and recovery process.

Keep reading to find out what she said…

Four months after Heather Rae welcomed her son, Tristan Jay, she started experiencing extreme fatigue. “I remember saying to my assistant, ‘I feel like I’m dead,’” she said.

The real estate agent added, “My brain was so tired. My body was so tired. I was exhausted all the time and no amount of sleep could make it better.”

At the time, she was really struggling to film her show, The Flipping El Moussas. “Filming was absolutely brutal because I could barely get out of bed,” she told Today.

Heather Rae attributed her symptoms to recently giving birth to Tristan. She recalled, “I was like, ‘I’m probably just foggy because of mom brain.’”

However, she was also having problems with her milk supply, which stumped her. After getting some blood work done, she learned that her pregnancy had triggered Hashimoto’s disease, a disorder in which the immune system attacks the thyroid gland and causes symptoms like hers.

“When she told me what I had, I was in total shock,” Heather Rae said. Fortunately, since being prescribed the proper medication, she has been “feeling much better.”

Heather Rae recently reacted to being left out of the Selling Sunset Season 7 poster.