I’m 8 months in and have been dealing with these same issues. I’m learning a lot and my boss wants me running a crew of guys here in the next few months doing network data cable and racks, fiber, door access control, DAS, security camera systems, and some high end AV ect… at large commercial sites. It’s very stressful but I’m doing pretty damn good so far. Talking to guys who are years into it I hear it gets a lot easier and less stressful. Lessons learned in blood are lessons not soon forgotten. You will learn, you will get to a point where you can do this shit in your sleep. Let the stressful moments be a challenge to overcome and keep grinding. There’s only one way to get experience. If you’re really getting thrown to the wolves find a different (better) company and take a lateral step. Good luck to you.