Leaning into character flaws

Hey guys! I'll keep it short: I've been playing with a really cool group for about a year now. They're all really nice people but I feel like I'm not roleplaying well and really want to work on that.

I'm playing the classic "snotty elf" but I'm really struggling with leaning into my character's flaws. I do suffer from social anxiety and most of my day-to-day social interactions are me desperately trying to be kind and agreeable. That really clashes with my character and I'm too scared to play her as the first-unlikeable-but-eventually-not-a-total-asshat arrogant twat that I had in mind when I created her. Basically I'm afraid of coming across as an actual rude person lol. I only really know the DM and barely interact with the other players out of DnD.

Do you have any advice on how to approach this?