Of course it is a sin...but is a result of a reverse faith and just living in sin generally. Faith precludes worry, but the church mostly has failed to teach it well. The fhu.com does a great job of teaching faith with their Be Still exercise. I have been practicing this silent prayer for many years and I never worry. Even if life gets tough at times, I know that worry will not be helpful and will block the natural ways and answers.
I’ll take a look and see. I grew up with worry.