Child support legal help?

I'm in debit with credit card bills and I owe the IRS a very large amount of money on top of that I’m trying to go to school plus I pay rent in nyc. My job doesn’t pay much. And now my bitter Baby Mamma wants child support just to make it hard on me. My question is Can see get much???? Let’s say I make 700 biweekly. BTW I do help her when I’m able. Truth is she’s bitter because I moved on in my life. I’m a good man with a good woman now. She had the baby just to be spiteful, but I accepted my child anyway.