This is horrible, but it is entirely possible. You could actually end up in jail. When a New Jersey citizen is attacked and then fights back, they might be arrested and charged with aggravated assault or even murder. Information can be found here.
Criminal Defense in Newark
The best way to avoid prosecution is to hire an attorney immediately. Even before you talk to the police, you need to have an attorney at your side. The attorney can advise you on what you can or cannot say to the police. The criminal defense lawyer will know how to convince the prosecutor that what you did was lawful. See here for information about The Castle Doctrine in Criminal Defense.
As long as you did not use excessive force, your criminal defense attorney can work for your release. But be careful about excessive force. If a person just shoves you, that doesn’t mean you can shoot them.
Weapons in New Jersey
New Jersey is one of the few states that has an active assault weapons ban. So, if you have defended yourself with an illegal weapon, you can still end up going to jail.
There is a website that lists all the weapons that are banned in New Jersey. If you have used an illegal weapon, your criminal defense attorney in Newark will have a hard time proving self-defense.