My feeling is that perhaps you’re too hard on yourself in this case. Don’t be afraid to step out of your comfort zone. Research topics that you’re unsure of and cite resources if that would benefit the piece.
Keep writing and putting yourself out there. It takes vulnerability and courage to do so. And if you start writing something but then hit a challenge or are unsure, you can leave that piece unfinished as a draft, and then finish it if and when you want to.
Don’t let this one drag you down. Don’t judge yourself harshly. You’re your own worst critic and the one who will remember the longest. Let it go.