To obtain a Protective Order there needs to be some threat of physical harm to you, so this would not appear to be an option.
Get the child support and let him file for custody (which usually is a bluff anyway). Your child has a right to that support.
You can call Child Protective Services. They will investigate and have the power to remove children in cases that are appropriate. Without CPS involvement, you must comply with the existing court orders.
Is this an appeal from the Juvenile and Domestic Relations District Court to the Circuit Court? If so, you probably want a Child Custody lawyer. Appellate lawyers generally handle cases in the Court of Appeals and Supreme Court.
Unless the decree provides separate amounts for each child (which would be unusual), he has to return to court to have support recalculated, and a new Order entered. He would file a Motion to Amend support.
You can file a petition for custody in the Juvenile and Domestic Relations
District Court. The wishes of the child is one of the factors that the court can consider in making a custody determination. The court also will appoint a Guardian Ad Litem to serve as an attorney for the child. That attorney will conduct an investigation and will make a report to the court.
The court order remains in effect until the judge enters a new court order. Filing a motion does not change a court order. If you fail to obey a court order, you can be held in contempt of court anf punished by fine or imprisonmement. Not a good idea.
It can be changed ONLY if either she agrees or there is a provision in the Agreement that permits it to be modified. Even if the Agreement permits modification, you still would have to show a material change of circumstances since you agreed to it.
I am assuming in answering this that you do not have some legal defense to the validity of the entire Agreement ( such as fraud, duress) and that you just made a bad deal. Courts make adults live with their bad deals. They make a consultation with a...
First, any money put into the TSP during the marriage is marital property that is subject to division in a divorce. That is the reason that the TSP Board requires the spouse's signature. You can go to court and seek entry of an Order.