i know how you feel anon :) when i posted my first fic i was so fucking anxious. it was the worst. even now like 2 years later every time i post it is an exercise in anxiety lol. this is advice you might have heard a few times before but you should try out fic memes/kink memes. it's a good way to dip your toe in and not have to worry about anyone knowing who you are, if they will judge you, if somehow the shame of your HORRIBLE AWFUL FIC!! will follow you.

as an aside i personally tend to only write gen and never any sex but kink memes these days have lots of prompts to cater to that, if you are the same. good luck!