I should put more trust in my thoughts and ideas. Story ideas that I had in mine but doubted them were eventually made into books and movies by others. And when I watched these movies, I would scream in my head, “Hey, I had the same idea!”
One example was “Tales from the Crypt: Demon Knight” with Billy Zane. I had a similar concept but instead of portraying demons, I thought of vampires.
My version: Some people were trapped in a castle, and one of them had this special gadget that created a temporary force field (20 minutes each time) that protected them from vampires.
In Demon Knight, someone had a mystical bottle of blood that when poured on the ground would create a temporary force field to prevent the ghouls from crossing over.
There were other stories that I lost opportunity too. But you get the idea. Confidence is key.