Justin Bieber had a major health scare following his London concert last night (March 7), but he seems to be enjoying his hospital stay as best he can -- namely, shirtless. Because if he'll do it on a public street, why not in a medical facility?

A quick refresher course: Bieber collapsed during his London concert last night and was treated with oxygen backstage. He later performed the remainder of his show before being taken to an undisclosed hospital.

While it's still unclear what caused Bieber's breathing issues, sources say he should be fine to perform his scheduled concert tonight -- though he may have to scale back a bit on the choreography.

He tweeted about the scare:

Justin posted the above photo to his prolific Instagram account, letting his beloved Beliebers know that he's “gettin better listening to Janice Joplin.”

Considering he'd just passed out and the rock legend was way before his time (possibly way before his mom's time, too), we'll give him a pass on misspelling "Janis."