Amid dating rumors between his ex Selena Gomez and Zedd, Justin Bieber is reportedly upset because he is the one who introduced the two to each other.

"The Heart Wants What It Wants" singer and EDM DJ were reportedly spotted holding hands as they attended the 2015 Golden Globes after-party together on last Sunday.

According to HollywoodLife.com, Bieber, who previously collaborated with the famous DJ on a 2012 hit, is not happy about the recent claims.

"When Justin was working on 'Beauty and a Beat' with Zedd back in 2012, he bragged to Selena that he was working with a genius -- Zedd," a source said. "He talked about how brilliant he was and how they were going to make hit songs together. He went on and on about how creative this guy was, how cool he was. So now that Selena is actually with this guy is like a stab in Justin's heart."

Not only the he is mad but Bieber also reportedly feels intimidated by the "Stay the Night" hitmaker.

"Yes, Zedd is a threat to Justin. He's super talented and successful. He's got a ton going on and he's just a nice guy, with an awesome sense of humor. Plus he's sensitive and quirky, and Selena likes that kind of stuff in a guy," the source said. "What really infuriates Justin is Selena's song collaboration with Zedd. He feels like this whole thing is just a slap in his face. He was the one who was supposed to collaborate with Selena on a song, not Zedd. To the outside world, Justin is going to act like he doesn't care one bit, but in his inner circle, everyone knows he's hurting big time over the fact that Selena is with Zedd."

Does Bieber then think that on-and-off-again girlfriend Gomez will move on from him with Zedd?

"No he does not think Zedd will replace him," another source told HollywoodLife.com. "He's shocked that she's with Zedd to the point where he's been saying he thinks it's fake, that they're doing for attention."