Thank you for your question. Please permit me to assist you with your concerns.
To make it easier, please let me split your question into two distinct sections, specifically civil and criminal.
Under civil rights
and obligations, you could potentially sue the individual who caused harm to you provided that it was not in self-defense. In California small claims are up to $10,000, so if your case is worth more, perhaps going to a different and higher court would be wiser. This is a situation where there may also be a claim for 'assault' (which is the taunting and the verbal commentss against the other gentleman, but if he never threw a punch, it makes for a weak case. In addition a typical value for a case is from 3-5 times the medical bills, as that is considered to be the additional pain and suffering. There is always a risk that if he has no money, while you can sue, you may never collect. As for a 'chest bump', while it is technically a battery, if it itself never caused you injury, you can sue but damages would be minimal.
In small claims you can later pursue a wage garnishment, a bank levy, and judgment liens if you prevail. But you cannot sue for attorney fees, that is not able to be pursued at the lower courts. You also can sue them both as co-defendants especially if you believe that they acted in concert.
As for the criminal element, please do not forget that this is also a criminal matter. It may be wise to pursue charges and only sue once and if a conviction is obtained--that information can be brought into a civil case which would of course help strengthen your ability to ultimately prevail.
Hope that helps.