earmark - Cash you already spent but still think you have, like when y

Cash you already spent but still think you have, like when you buy a car and then realize you've already used up all your money.

I spent my paycheck on a new phone, but I still think I have money left.

She bought a fancy suit with her last dollar and still said she was rich.

He spent his bonus on a trip to Vegas and now thinks he has money to spare.