Alright, for starters I have autism and so I never realize if I'm just a douce, so if you guys think I'm an asshole I'll apologize.

Now on to the situation, we (me, she, my other sister, my stepdad) were playing a boardgame in which we had a disagreement about the rules. Everyone chose my side. So we move on. The rest of the game, all she does is target me, now normally I can just ignore that, but everytime she does that she just laughs at me. It doesn't help that she is super competitive. So at the end she wins, which is fine, idc about winning. However  at the end she just laughs at me and taunts me. So at this point I was already upset, and I explode. I start yelling at her, I think I called her a narcissist, and she called me a 'petty asshole'.
When our parents arrived I got all the blame.


Tl;dr

I kept getting taunted by my sister and I got angry. Now everyone is angry. Should I swallow my pride and apologize?