I don't really understand why you've gotten into an argument on the aircraft.
If you didn't have a business class boarding pass, why did you not resolve that issue prior to boarding?
Why did you wait till you boarded the plane with an economy class boarding pass and sit in a seat that wasn't allocated to you?
I think you also need to wake up and realise your not in Kansas anymore, pulling these kind of stunts in some countries could have resulted in an even worse situation then in HK. This is the reality of travelling abroad.
Please post some more information and clarify, because it seems very odd.