Re: I can't pay my charges and they charged me more than I can afford.
What you're charged for AdWords depends on what budget you set for clicks when you created your account. You set how much you would be charged when you set your own budget.
I am not certain why you would have set your budget for more money than you could afford to pay, but you do need to pay the bill, just as you would need to pay any costs you incurred for any product or service.
I am not aware of any kind of "payment plan" but you can try contacting Google directly to talk to them about it.
Google AdWords Top Contributor