Heya,
I understand you're upset and I would like to offer some information on the matter. When the IFS looks into an audited match (a report will flag for an audit), it will scan through the chat history and the actions by the players of the game. If someone flames or triggers an IFS punishment, then there is something that was actionable.
With that said, according to the IFS FAQ, the third offense is a "two week suspension." However, sometimes behavior can skip tiers and someone can be given a two week suspension for their behavior. From what I can tell, your retaliation against those individuals was extreme enough to either skip punishment tiers or it is likely you have a history of either flaming/trolling or you have retaliated in the past.
My best advice, is to /mute all and ignore the players who are doing this to you. It isn't worth getting punished because people want to flame you. I understand it's difficult and frankly there are times where I want to retaliate and call them names or cuss at them. However, I don't and I mute them all instead, so I can calm down and focus on the game. I would hate to see someone getting perma'd on an account, because they chose to retaliate and flame other players. I wish you luck and please take my advice under advisement.
Thanks,
Galacius