Final spousal support?

I have 50:50 custody of my kids. I pay the daycare and health insurance of the kids which is 500 bucks plus 150 interim spousal support. My ex wife is now wanting final spousal support. I can't afford this we have the kids 14 and 14 and i'm overdrafting every month. I don't have a lawyer and she does becasue her mom is paying for it. is there any way I can find out what the payment calc is for 50:50 in louisiana?