This question cannot be answered without knowing more facts, and reviewing the specific language in the insurance policy. Under some facts there could be coverage. Under other facts there would not be coverage. The language in insurance policies varies from company to company, and some policies provide more coverage than others. Most personal injury attorneys will review your case facts and insurance policy without charging. That is how you will obtain a definitive answer. Good Luck.
Under some circumstances you can set aside a release, even if you have been paid money, and signed a written release. You don't mention your age, or what pressure was used to get you to sign the release so there aren't enough facts to go on. Also, under some circumstances a parent can sue for the harm done to a child. There isn't enough detail in your question for any attorney to answer your question definitively. It makes sense for you to talk with a personal injury attorney licensed in...
Your health insurance will likely claim a portion of the settlement. They want the money they paid for your health care back if they can get it. Whether the health insurer is entitled to any money back depends on the wording of their contract, the law applicable to your specific legal claim, and the amount of insurance the at fault party has. The health insurer may be entitled to a large portion of the settlement, or nothing. It depends on facts that you haven't set forth in your question....
I seldom answer emails about claims because they rarely contain enough information to give a useful reply, and because the "contact an attorney" advice sounds so self serving. But here goes. The issue is what do you want to do? Recover a fair amount for your injuries? Report the other driver for driving without insurance? Get the police to issue a ticket for not having isurance? Do all three? It is also not clear from your email whether your UIM settlement will be a full and fair...