I cant believe all these women here telling each other to go to court unrepresented as if it was just filling out paperwork. Child custody is not a joke! Maybe you got lucky and things were easy but most likely than not, cases start fine and then go down south. So please, stop giving such a bad advice.
If you are only going after child support, some states have a Child enforcement office that will let you file everything and get an administrative order without even having to go to court.
OP. If you cannot afford a lawyer try to see if there is legal aid available for you. Maybe you will be able to qualify. http://legalaid.uslegal.com/
If there is not free legal aid for you, a lot of lawyers have a free first consultation that you could use. Lawyer up and see what your options are because usually when it comes to legal things, you rarely have a do over.