IWTL how not to break down during confrontations

I (25F) really want to grow up and stop being seen as some stupid child who can’t do anything. And one of the things I need to learn how to handle is confrontation.

I can’t handle any sort of confrontation. When people yell at me I automatically break down in tears and that just makes them more angry.

When people get angry and argue with me, I start crying because I’m never good with arguments and I cry when I’m frustrated.

When people ask me repeated questions in an angry manner, it makes me really uncomfortable and feel like I’m on trial being interrogated usually leads to me, you guessed it, crying and giving up.

This isn’t because im an undisciplined child who was never yelled at before. Please, I was yelled at all the time growing up. I’ve always reacted this way. Now I’ve always been sensitive and struggled with emotional dysregulation (autism) but I can’t use that as an excuse. I need to learn how to actually mature and not start crying. Deep breathing doesn’t help. The only thing I’ve found that helps me stop crying is poking myself really hard with a pushpin or digging my fingernails into my skin until it hurts but neither of those methods are exactly healthy.