If you lack the confidence then your training is amiss. Knowledge dispels fear.
Not sure I agree. My training was comprehensive, but I was nervous as f**** during my first solo flights after my PPL, especially to busy commercial airports. I just happen to be able to get on with, other people quite understandably and reasonably might shy away choose less 'challenging' flights in their early hours. At the other extreme are those who are virtually Baderesque in their approach!
Knowledge is theory, doing it is experience. Experience dispells inappropriate fear (and reinforces justified fear!).