Ariana Grande attends the 13th annual Billboard Women in Music event. AP

Singer Ariana Grande is telling her fans that she has a bad sinus condition that has made her "very sick” and might force her to cancel upcoming shows on her world tour. 

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Grande, 26, says in videos posted Saturday on Instagram that "my throat and head are still in so much pain.”

Ariana Grande performs during a concert. File photo/Reuters

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.”

Grande says she plans to see a doctor soon.

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.”

People magazine first reported on Grande’s Instagram videos.

Associated Press