I tried to break up a buddy and two other guys who were yelling at each other and getting in each others faces and I was sure there'd be a fight. I got between them and told them all to calm down and let the issue go. One of the guys shoved me so I punched him. The other guy came at me so I punched him too. I'm going to be charged with assault. But I only punched because they pushed and charged me. Was I acting in self defense?
Speeding / Traffic Ticket Lawyer
Self-defense is an affirmative defense - you have to raise it. This will come down to how your attorney defends your case. It should be raised absolutely. Whether the jury accepts it is the trick of the trade.
Basically, you can use non-deadly force to defend yourself from immanent use of non-deadly force against you to defend yourself. Typically, this would be the minimum amount of force necessary to prevent the harm happening to you. Your attorney will have to convince the jury that this is what you did.
This is too broad a question. It would depend on many factors:
How much force was used and was it reasonable force, etc. There are too many factors involved in something like this to determine self defense. Questions like this cannot be answered with a simple yes or no.