It's alright mate. I've been doing this for close to two decades and while I've certainly improved, I can't say I feel like I'm the biggest fish in the pond. And while you may have missed out on valuable writing experience, you do have more life experience, and what is writing fiction but writing about someone who never existed? 

Welcome to the guild! I'm sure you'll find something that catches your interest. We have all kinds of sections on writing advice, but as you mentioned, sometimes you just gotta do it! Most RPs I've seen are relatively judgement free, and as a GM it's always very rewarding to watch a roleplayer's skill grow over time. GM meaning "game master," the big cheese of an RP if you were curious. There aren't too many terms that get tossed around that much, but anyone who wants +1 players in their RP would have no problem showing you the ropes.