A big behavior associated with social anxiety is an obsessive monitoring of how other people behave, particularly how they respond to you and what you say.
I'm sure we're all familiar with this..... it goes like....
Me: [says something]
Everyone else: [no response]
Me, in my head, with social anxiety: "oh my god why did i say that?? im so awkward! nobody responded, they must have thought it was stupid! next time i should keep my mouth shut omgg!! i'm so embarrassed maybe i should leave.."
OR........
Me, in my head, WITHOUT social anxiety: [Nothing]
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.....Because it doesn't matter. People don't always respond to things other people say. It's not because what you said was stupid or wrong. You weren't wrong to say it.
People who talk a lot, don't talk a lot because they get amazing responses to everything they say. Often, when people do talk a lot, they get no response to, like, half of what they say. It's just that they don't care. They talk anyway. They probably know that people tune them out half the time, but it just doesn't matter. It doesn't embarrass them. They don't even notice when people don't respond, because they're not monitoring it.
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The monitoring behavior is one of the sneaky ways that SA keeps you trapped and miserable.
It convinces you that you were wrong to speak up, and that the answer is to shut up and stop speaking.
But the opposite is true. If you speak more often, you'll start to see that sometimes people do respond, sometimes they don't, and either way, it's totally fine.
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I can predict some responses to this:
"When I speak up, I say something really weird and people laugh at me!"
This is another trap that SA sets for you, one that's harder to get out of.
It happens for one of two reasons:
What you said wasn't weird, but you said it with so much tension and anxiety that it seemed weird.
What you said was kind of weird... not because you're inherently weird......but because you're so unused to speaking that your skills are a little rusty.
Either way, the solution is to speak MORE, not less!
But the social anxiety will keep you trapped because it will keep convincing you that it was SO HORRIBLE that people thought you were weird.
Someone without social anxiety would never fall into this trap at all, because even if people think they're weird, they don't care. They just keep speaking anyway.
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When you're trying to change beliefs, it's not about forcefully convincing yourself. As long as you're forcefully trying to convince yourself, there's always going to be another voice fighting back. Rather, it's about analyzing objectively and seeing what actually makes sense. When you see what makes sense, you don't have to convince yourself of anything, because it will just be self-evident.
Seeing what actually makes sense becomes possible when you observe the situation objectively..... and not just once, but many times..... and think about it critically, rather than just responding like a knee jerk according to your conditioned SA behaviors.