Is age finally catching up to Billy Joel ... At one point in the song, Joel, 75, threw his mic stand to entertain the crowd, however, this caused him to lose his footing and he abruptly landed ...

Joel McHale is already in Atlanta shooting "Scream 7" and will soon be taping Fox's "The 1% Club," a game show.

But after spinning his microphone stand and tossing it toward ... and he then appeared to get back up on his feet as the footage concluded. The rest of Joel's set continued on as planned ...