A source tells PEOPLE the R&B star — born Abel Tesfaye — scheduled performances around her medical emergency.
A rep for the Weeknd did not immediately respond to PEOPLE’s request for comment.
“It was a super serious operation,” the source tells PEOPLE exclusively, “and all her friends were worried.”
On Thursday, Gomez, 25, revealed that she underwent surgery following complications from the chronic autoimmune disease lupus.
“I’m very aware some of my fans had noticed I was laying low for part of the summer and questioning why I wasn’t promoting my new music, which I was extremely proud of,” Gomez captioned an Instagram post. “So I found out I needed to get a kidney transplant due to my Lupus and was recovering. It was what I needed to do for my overall health.”
The Weeknd was in between dates of his Starboy: Legend of the Fall Tour from July 22 through Aug. 6, then again until Sept. 6. The Grammy winner’s Grey Goose-sponsored show was canceled last-minute on Aug. 26 — and though he was initially announced as a performer for the 2017 MTV VMAs, he was a no-show Aug. 27 at The Forum in Inglewood, California.
Gomez also opened up about her kidney donor, her longtime friend, actress Francia Raisa.
“There aren’t words to describe how I can possibly thank my beautiful friend Francia Raisa,” the “Fetish” singer wrote. “She gave me the ultimate gift and sacrifice by donating her kidney to me. I am incredibly blessed. I love you so much sis.”