Ariana Grande told her fans she is "very sick" due to a bad sinus condition that may force her to cancel upcoming shows on her world tour.

The 26-year-old said on her Instagram Story on Saturday that “my throat and head are still in so much pain.”

ARIANA GRANDE ROCKS 'TWILIGHT ZONE'-INSPIRED HALLOWEEN COSTUME

While she sounds OK, “I’m just in a lot of pain and it’s difficult to breathe during the show,” she says in a message to her fans. “I just really don’t know what’s happening with my body right now and need to figure it out.”

An error occurred while retrieving the Instagram post. It might have been deleted.

Grande says she plans to see a doctor soon.

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She adds: “I’m scared that I might have to cancel some things, so this is kind just a heads up of like I don’t know what’s happening with my body, and I’m really disappointed and freaked out of why I can’t get better because it’s been over three weeks at this point.”

The Associated Press contributed to this report.