A judge changed order to pay $500/mo from the $100/mo originally ordered,knowing I can't pay that much?

Unfortunately you fall into the category of do the crime, do the time. You can petition the court to have the costs reduced but you did what you did. You punched the guy and damaged his nose. It doesn't matter how he paid to have it repaired -- if not for you none of this would have happened. If having name recognition would have gotten you more leniency, I doubt you would be complaining. Best to suck it up and try to abide by the court order or hire a darn good lawyer to get you out of a mess of your own creation.