Something’s off. Kendall Jenner opens up about the debilitating effect of a mystery illness in a preview for the Sunday, November 6 episode of Keeping Up With the Kardashians.

“I wake up in the middle of the night, and I can’t move,” Jenner, 20, says in the clip above of her undisclosed condition.

The sneak peek then cuts to a scene of the model chatting with momager Kris Jenner about her health dilemma. “I think you’ve just got anxiety,” the reality TV matriarch, 60, tells her daughter.

However, Kendall thinks her symptoms are more serious. “Everyone says I’m fine,” she tells Kris. “But I don’t feel fine.”

While the catwalk queen’s ailment remains unclear, she previously told fans that she deals with anxiety attacks stemming from trypophobia.

“Anyone who knows me knows that I have really bad trypophobia,” she revealed in an August 15 post on her official website and app. “Trypophobics are afraid of tiny little holes that are in weird patterns. Things that could set me off are pancakes, honeycomb or lotus heads (the worst!).”

The brunette beauty added at the time: “It sounds ridiculous but so many people actually have it! I can’t even look at little holes — it gives me the worst anxiety. Who knows what’s in there???”

As viewers saw on season 12 of KUWTK, Kris had to accompany Kendall on a work trip to Europe because of her issues with anxiety.

“[I’m going to London] for the day because Kendall had a really awful night last night flying to Paris because she gets really bad panic attacks and anxiety,” Kris explained on the show. "I don't know what to do."

Keeping Up With the Kardashians airs on E! Sundays at 9 p.m. ET. 

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