I recently took child support out on my sons father. I turned the application in around May 1,2011. We had to do a dna test being as he want on the birth certificate. My question is would he have to pay me back child support? Mind you my son was born in November 2010 and he had yet to buy anything or even see him. And yes the dna showed a 99.9%

Back child support is up to the judge and the jurisdiction it is in. Not all courts allow for it. Also the judge may ask why you waited so long to file.

ANY question on law needs to include your general locale as laws vary by area.

As noted it depends. If you filed in May you should get support back to then. But to get support prior to your filing will depend on prevailing laws.

It is very likely that you will be awarded support to the date you filed.

We are in Georgia

... support to the date you filed.

And from as well?