Your trial stands alone. No matter what is decided with regard to the theft, it has almost nothing to do with whether or not you assaulted this woman. You know you didn't. The judge and jury don't know either or you really and it is very possible that the kid will be found guilty of stealing and you will be found guilty of assault. Those are not mutually exclusive. It doesn't matter if this lady has a record a milt long, if she is assaulted, she can legally pursue justice for that assault. It isn't dismissed because she is a bad person or "deserves it". To be totally honest, from your description of the tug of war over the bike it is entirely plausible to believe she was injured as a result.
From her point of view, her kid was given a bike by a friend and some guy in a truck carrying a gun tried to take it and claimed it was his. She tried to prevent you from stealing her kid's bike and you injured her in the process. Like it or not, that is a sympathetic case. The fact that you took matters into your own hands rather than wait for the police just makes you look like a hot head and a bully. Or at least, I am sure that will be the tactic that will be taken.
The proper thing to have done would be to call the police when you spotted what you thought was the bike. Let them investigate and see if it was or not. Let them deal with the mother and son.
From her point of view, her kid was given a bike by a friend and some guy in a truck carrying a gun tried to take it and claimed it was his. She tried to prevent you from stealing her kid's bike and you injured her in the process. Like it or not, that is a sympathetic case. The fact that you took matters into your own hands rather than wait for the police just makes you look like a hot head and a bully. Or at least, I am sure that will be the tactic that will be taken.
The proper thing to have done would be to call the police when you spotted what you thought was the bike. Let them investigate and see if it was or not. Let them deal with the mother and son.