I don’t work in payroll or accounting, but I’ve been doing some overtime lately and kept running into something a lot of people seem to notice: You put in extra hours… and your paycheck doesn’t really feel like it goes up as much as you’d expect. At first I figured I was just misunderstanding taxes or something with brackets. But the more I looked into it, the more it seemed like the issue usually isn’t “extra tax on overtime” — it’s how withholding gets calculated on a single pay period. Basically, when your paycheck is higher than usual, payroll systems can treat it like you’re going to earn that higher amount all the time, so they withhold more temporarily. That can make your net pay look smaller than expected, even though your actual tax rate hasn’t changed. It’s more of a timing/estimation thing than anything else.…