As others have said, it is normal for your age.
I want to second this. An important part of your 20s is learning how to interact with the world as an adult. That means access to many more things, but also the requirement to develop personal skills to responsibly use what is now available to you.
My personal tip is to try to wait at least 24 hours before buying something or sending that email. If it still seems like a good idea it has at least matured over a nights sleep and some thought.
In my 20s, when I was overspending, I did something similar to this. Anytime I saw something I wanted to buy (not required for life), I would write it on a list. I allowed myself a purchase of 1 item off the list a week, but the rule is that the item I purchased must have been on the list for at least one week.
I was surprised how many things on the list I found I didn’t want anymore even after a few days, and since they were just on the list, instead of being purchased, I ended up saving quite a bit of money. I also didn’t feel denied things, because I was still allowing myself to buy one thing off the list.
You know your industry better than I do, but my industry-agnostic answer would be: “Yes, absolutely apply if it moves your career forward”. Even horrible bosses/departments can be useful as stepping stones. Many times these are open and others are avoiding them because the environment/boss sucks. If you can do a year in that department/boss as a springboard to a higher position elsewhere, I typically think its worth it.