Justin Bieber has some anger issues he needs to work out, apparently -- so he did the best therapy on Sunday, and went for a hike.

After going off on the paparazzi on Friday night as he made his way into nightclub Delilah, Bieber seems to have released some stress with a stroll through nature with some pals. And man was he outfitted for it! He wore friend Floyd Mayweather's The Money Team sweatshirt, which was quite colorful, along with sport shorts, leggings and knee-high socks. Wow -- it's a lot!

And can we just say it? What's up with Bieber's hair? It's like he's going back to the 14-year-old version of himself. He's a walking throwback. We no likey ...