The first time I TA'd a lab course, my professor mentioned how much more confident I seemed. My first TA with him had been Intro, my second semester of grad school. Although I had already TA'd for one semester of Intro at that point, the first year of graduate school was not particularly distinguishable from college, except for the lack of a supportive social group. It was gratifying but hardly surprising to discover I appeared more confident several years later; by the time I started requesting TA opportunities I was a grown-up, or at least I felt like one.
Being a grown-up does not help with some chores. I've matured enough to teach confidently with excellent FCQs, and even request time at the next faculty meeting for my Lead TA duties. Time comes to ask faculty for letters of recommendation, though, and I'm back to being a college student. Twenty minutes to compose a three-sentence email, loitering around office hours trying not to appear to be loitering...oh, college Student. How I do not miss thee.
Perhaps next time it will be easier. Asking for letters is hard for two reasons: First, because it's asking an unrequited favor, and second, because it's presuming a positive opinion. There is not much I can do about the second, beyond watering my ego and hoping it grows (though not too much), but this time at least I had ways to repay my writers. My prof, upon hearing that I could provide my course materials for his reference and declaring me one of the best TAs he's had, asked for copies he could give out to future TAs. And asking my Lead TA boss put me on her radar, as someone to turn to when she needed a last-minute training assistant.
If I do not get a job, it will not be for a lack of good references. And it might not even be due to a lack of confidence.