But the court can "impute" an income to you based on working full-time.
If the state where you live has adopted the UIFSA (a majority of states have), your modification action must take place in that state under its child support laws.
But child support isn't necessarily recalculated using the parents' income figures at the time of the modification. Most states allow courts to "impute" (add) potential income to "underemployed" or "voluntarily unemployed" parents when calculating or recalculating the amount of child support. "Underemployed" means that the parent isn't working to his or her earning capacity. The court can "impute" "potential income" to the underemployed parent's income when determining that parent's gross income for the child support calculation. "Potential income" is income that the court finds the parent would have earned if fully employed, as determined from:
The concept of "potential income" prevents parents obligated to pay child support from "voluntarily" reducing their income and thus lowering their child support obligation.
Some state courts have ruled that being disabled doesn't mean that a person is unable to earn any income. The court reasoned that being disabled for the purpose of receiving social security disability benefits only means that a person is unable to meet the government's "minimum income level." So a certain income level may be imputed to a parent receiving social security disability benefits.
If these disability benefits are coming through Social Security, your children may qualify for their own benefit check as your dependents.
Even if you can get the court to reopen the case, recovering the support you've previously paid is a longshot. First, it's entirely likely the mother doesn't have the money. Second, the right to demand DNA testing was yours in the first place, so there isn't a tremendous argument for "rewarding" you for failing to assert your rights in the beginning.
There are states, however, that allow an increase based just on an increase in ability to pay. In many states, the person requesting an increase must show there's been a "change in circumstances." In Ohio, the usual method is to show that the child support amount calculated is 10 percent greater than the amount paid, or that there is a change in the needs of the child.
On the other hand, if you and your ex-spouse have agreed that you'll pay more than the court order provides, you don't have to be in a hurry to change the order. If the non-custodial parent agrees to an amount in excess of the order and then refuses to pay it, the custodial parent can always file then to change the order.