Q: I think I made some mistakes with my new staff when I started this job, and they now seem to lack confidence in me, which has been communicated to my boss. He now seems to have some concerns. How can I get things on track?
A: Demonstrate your management skill and technical knowledge to establish a positive base.
The inner game
Let go. If you tend to beat yourself up, forgive yourself. Instead, focus on your breathing and move to a deep state of calm. From there, envision the working relationships you'd like to foster, imagining the day-to-day interactions with each individual as well as the overall culture you'd like to shape.
Now look realistically at the situation. If you've been feeling embarrassed or ashamed, that may color your objectivity. Write down the course of events from when you started through the present as though you were someone else neutrally describing it. While you're likely correct that there were missteps, it may not be the case that the outcomes are as dramatic as you originally felt.
Analyze the specific mistakes. Did you come in too tentative and undermine their confidence in your ability to do your job? Or was it the opposite, where you came in too hard but uninformed? Is the perception of you fairly unified, or would different people be likely to provide different feedback?
Consider why you interacted in this way. Is it your way to be open and honest, but under the stress of a new job it showed up as oversharing? Or are you a take-charge type of person, but nervousness made you come on too strong? Spend some time really understanding this because it'll help you turn the overuse of a strength into an asset.
Finally, make sure that you're not sabotaging yourself in any other ways or in other settings — this could be a pattern that undermines the strengths you bring.
The outer game
Consider your options for moving forward. At some level, there can be a "least said, soonest mended" dynamic. However, if the issue goes beyond one minor gaffe, this wouldn't be sufficient. Instead, modify your interaction style and set a new starting point for you and your team's interactions.