You actually have better English than most native speakers are capable of commanding. And your writing is very up to snuff. Don't worry about failure, just do it. If you see a writing contest, just join it anyway. What's the worst that can happen? You write an article everyone else gets to read that doesn't end up getting picked? So really it's no different than not joining the context, except the fact that if you don't join, you don't have the chance of winning. There is no lose in this situation, it's a win-win.

Stop the self sabotage and just freaking do it already. I'll still follow you, I'll still end up reading it, I'll still end up commenting and I'll still end up likely giving you yet another upvote.