One thing (among all the other great suggestions) you can do is to make sure you’ve got a budget in place, so you understand what your projected finances look like.
It’s not just about making sure you’ve got enough money either, it’s about spending it guilt free, because in your budget, you’ve already spent it. This helps me budget for things like haircuts, and other self-care things without worrying about it or feeling guilty. The net effect is that I look after myself in new ways and feel more confident about where my money is earmarked. This could be a way to help shake your feeling.
I use YouNeedABudget (YNAB: https://www.youneedabudget.com/) which gives me a lot of confidence about my finances.
It’s not just about making sure you’ve got enough money either, it’s about spending it guilt free, because in your budget, you’ve already spent it. This helps me budget for things like haircuts, and other self-care things without worrying about it or feeling guilty. The net effect is that I look after myself in new ways and feel more confident about where my money is earmarked. This could be a way to help shake your feeling.