The singer and rapper is experiencing difficulty breathing after his tumble in St. Louis last weekend.

Post Malone is back in the hospital one week after he injured his ribs on stage.

The rapper and singer, real name Austin Post, canceled a show in Boston on Saturday night after he awoke to "cracking sounds on the right side of my body" and experienced a stabbing pain. "I felt so good last night, but today it felt so different than it has before," he shared on Twitter. "I'm having a very difficult time breathing, and there's like a stabbing pain whenever I breathe or move."

The "Sunflower" singer said he was in the hospital and apologized to fans for cancelling the show at TD Garden, noting that tickets will be valid for the rescheduled date once that becomes available. "I'm so f---ing sorry. I love y'all so much. I feel terrible, but I promise I'm going to make this up to you."

Reps for Malone didn't immediately respond to EW's request for an update on Sunday.

On Sept. 17, Malone received medical treatment at a hospital after he tripped on an uncovered hole, which was used to lower his guitar, on stage during his concert at Enterprise Center in St. Louis. "Thank you for putting up with my dumb ass," he said in a video shared on Twitter at the time. "There's this big ass hole so I go around there and turn the corner and bust my ass... winded me pretty good."

Noting that he just returned from the hospital, Malone assured fans that "everything's good" and "we can keep kicking ass on the tour." The singer was apologetic to concert-goers: "Thanks so much for coming to the show," he said. "Next time I'm around, I'll we're going to do a two hour show for you so we can make up for the couple missed songs."

During a performance of "Circles," the Grammy-nominated artist tripped on the hole and fell hard on his ribs. He laid on the stage for several minutes as medics rushed to his aid. He was escorted off the stage, and after a few minutes, returned and, like a true "Rockstar," resumed his abbreviated set that included "Rockstar" and "Cooped Up." He held his ribs and visibly winced at times, according to attendees on social media.

Malone's manager Dre London confirmed that his ribs were bruised, but fortunately not broken. "Thank you everyone for all your well wishes!" London wrote on Instagram, alongside a photo of the two backstage. "In true Posty fashion loving his fans he finished the show! I truly don't know any artist like him. Talking to him few hrs ago he was still saying Dre don't go hard on em' explaining more then saying "the show must go on! let's all keep him in our thoughts as we know he will wake up in pain."

Sign up for Entertainment Weekly's free daily newsletter to get breaking TV news, exclusive first looks, recaps, reviews, interviews with your favorite stars, and more.

Related content: