Advice: Dale Carnegie has a book out on how to live above worry. “How to stop worrying and start living”
https://en.wikipedia.org/wiki/How_to_Stop_Worrying_and_Start_Living
in it, he tells the reader how to live in day tight compartments. Meaning, you live day to day, ask yourself what you can change (by worrying (answer is nothing)); and how to prepare for it, overcome it, etc.
yes, this field is highly competitive But you made the final cut. Don’t doubt your abilities.