Even if he brought it on himself, Justin Bieber has had a pretty rough start to his year, so you’ll have to excuse him for partying with his shirt off. He just doesn’t care right now!

The 19-year-old singer (who started off his night fully clothed) was spotted hanging out with a bunch of rappers and their entourages at a party thrown by Diddy at Vanquish nightclub in Atlanta earlier this month (Wed. Feb 5).

And while everyone was else was poppin’ bottles, the Biebs stuck to water — specifically Diddy’s AQUAhydrate — but as for weed, we’re pretty sure he hit the blunt a few times, which explains the need for water. You gotta stay hydrated so you don’t get keep that weird “cotton mouth” feeling.

T.I., Rick Ross, his MMG artists Wale & Stalley, Jermaine Dupri, Trinidad James and Lil Scrappy and others were all in attendance at Diddy’s party, as well as the rap mogul’s girlfriend Cassie, Justin Bieber’s (rumored) girlfriend Chantel Jeffries, and “Love & Hip Hop: Atlanta” stars Erica Dixon and Karlie Redd.

CHECK OUT A BUNCH OF PICS (COURTESY OF PRINCE WILLIAMS & ATLPICS.NET) BELOW: