Child support modification

In Nov 04 my then wife took me to court to establish child support. At the time, I lived in Virginia and she lived in NC. She took me to court in VA and a child support order was drawn up and I have been paying since(there was no sep agreement at the time). A separation agreement was drawn up in Jul 05 and signed and was incorporated into our divorce in Nov 05. (our divorce was filed in North Carolina) The separation agreement spelled out child support, how and when it should be paid and made reference to the VA court order. She is now taking me back to court to modify the VA court order. My question is this; Is the VA court order, dated Oct 04, the controlling order? Or is the separation agreement, dated Jul 05, filed in NC, and incorporated in Nov 05, the controlling order? I don’t have a problem with modifying the child support, but there are specific guidelines in our separation agreement regarding requests to modify and how we should only go to court if an agreement cannot be reached…well, she has chosen to just take me to court, mainly because I now live in California and the “inconvienence” seems to please her. I also want to make sure we are doing things correctly. Thank you for your time.