1. Test your code. I'm a senior engineer and the only way I know how to make sure my code works is by testing it. I use unit tests for this. If you don't like unit tests, find some way that works for you.
2. Try to get someone to review your work. When I'm working on something thats completely new, I ask someone I know and respect to review it and indicate which parts I'm unsure about.
3. First few months you may have to work harder. When I join a new team, despite being a senior engineer I spend time outside of work going through references to refresh/learn things so that questions I may end up asking will not be totally off the wall. After the first few months this becomes less of a problem until perhaps the next new thing comes up.
As for the mistakes you made, specially that QA/prod stuff don't worry too much about that. It's not only your fault. It's seniors job to create a working environment that's safe. On the teams I join, specially after I become a senior there, I push for safety measures whenever someone screws up unless it's deliberate or gross negligence. The fact that you feel bad about it shows that you did your best. I have seen once one of the most talented devops engineers brought a prod server down instead of staging because he is too quick on the terminal with many terminals open in his terminal multiplxer. Once a very talented db admin dropped an important table by mistake fortunately in dev and had backups. Things happen, and leaders/seniors should try their best to secure the environment.
Your job right now is to broaden/deepen your knowledge, ask intelligent questions, test your work before submission and keep calm and carry on.
1. Test your code. I'm a senior engineer and the only way I know how to make sure my code works is by testing it. I use unit tests for this. If you don't like unit tests, find some way that works for you.
2. Try to get someone to review your work. When I'm working on something thats completely new, I ask someone I know and respect to review it and indicate which parts I'm unsure about.
3. First few months you may have to work harder. When I join a new team, despite being a senior engineer I spend time outside of work going through references to refresh/learn things so that questions I may end up asking will not be totally off the wall. After the first few months this becomes less of a problem until perhaps the next new thing comes up.
As for the mistakes you made, specially that QA/prod stuff don't worry too much about that. It's not only your fault. It's seniors job to create a working environment that's safe. On the teams I join, specially after I become a senior there, I push for safety measures whenever someone screws up unless it's deliberate or gross negligence. The fact that you feel bad about it shows that you did your best. I have seen once one of the most talented devops engineers brought a prod server down instead of staging because he is too quick on the terminal with many terminals open in his terminal multiplxer. Once a very talented db admin dropped an important table by mistake fortunately in dev and had backups. Things happen, and leaders/seniors should try their best to secure the environment.
Your job right now is to broaden/deepen your knowledge, ask intelligent questions, test your work before submission and keep calm and carry on.