You are already miserable, what you wrote is fixed by contentment, not necessarily money. The question is the $300 now making you less miserable than using that money to pay off debt sooner or see a savings account go up again? Would you be happier in six months with $1800 less debt, would that free up more money by removing a payment?

Small stuff isn't always the problem, but for a lot of people it is. Some people need bigger changes, but those are often scary.