I don't practice in your state, but here is my answer nonetheless.
If you already have an agreement in place, it should be binding upon both of you as it stands. You may have a defense to it if you're unsatisfied because you signed it without an attorney, however, that would be a long road to overturn it after some time has passed.
I suggest you hire an attorney and work our a payment plan with him/her so you have competent counsel to represent you. Otherwise, you'll likely have a problem on your hands.
You can contest anything. I do not practice in SC but orginally am from SC. I practice in Florida. However, you can ask for a mediation with her and her attorney and if you can not come to a settlement then let her attorney request a hearing on the matter. You can represent yourself as he will have to notify you of the hearing. Most judges will give the leave way to explain your situation. Go on line and get the financial documents required and fill them out and ask her attorney to do the same. You will need this in order to show what the disparity is in the income. As to anger management, and not knowing the issue here, do the classes and get them out of the way. Then request that she too attend these classes and complete the course. Ask for a certification of her attendance. Also is you can not afford an attorney, you can apply at any legal aid office in your area and see if you qualify for a pro bono attorney. Also, call some of the local attorneys in your area and see if they offer payment plans. With this economy, I am sure you will have no problem.
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