United Kingdom, Nov. 2 -- Justin Bieber gets nervous being "vulnerable" online.

The 31-year-old pop star has been candid with fans about his emotional state of late and now he has admitted mean comments get to him.

During a recent Twitch session, he said: "Going on Twitch is vulnerable as hell because people who just feel s****y about themselves project and then they write mean-a** things.

"It's already hard enough to put yourself out there, and then you gotta read all this."

The Sorry hitmaker even starts questioning whether the things people are saying about him are true.

He said: "They were like 'Justin is not as exuberant. He will never be his exuberant self ever again. He's lost his charisma.' I was like, 'What? I just played ba...