Worrying only does one thing in my opinion. It causes unnecessary stress. Do the best that you can with that situation and ask for help if it gets that bad. Smile.
I used to worry a lot about whether or not I was making the right choices in college in regards to major and career. Because of all that worrying, and other factors I changed my major 8 times, and almost never started. The hardest thing for most people is taking the first step. I almost missed taking the first step. Luckily, I had someone willing to invest their time in me to help me get out of that phase and work toward something. In short quit worrying and go do. Just be sure to have a goal in mind.
What worries you to the point of not starting?
Far From Idle
Come. Find out why.