What do you view your salary as? Is that a measure of your earning power? Or the return on your education and preparation? The cashflow returns on the asset of your human capital (there’s further capital accumulation through learning on the job). Is it always about trying to increase this return? Or is there anything about getting more days of leave each year? And more benefits?
And do you think you can ask for more? Who is in the market for your labour? And who are you competing? If you consider that your employer is merely paying an ongoing subscription on your full time services as an employee, would that help you think about how much you’re going to ask for?
Why does it seem that the work you do to earn that salary also matters a lot? What actually drives that perception? If you earn $6000-$8000 a month as a construction worker, would you take it up? Assuming you’d be trained from scratch. What kind of work gives you the sense of balance between your salary and the output being produced? How are they shaped by your own thoughts and the people around you?
Many questions and it takes a lot of adulting to answer them. Some of us might never even come to arrive at the answers despite a lifetime of work.