I need help with my anger...?

ok so my step-dad is pissing me off...he thinks he own everything in the house and he hasn't bought on Single thing in the house and he yells if we exhale to loud. Also my mom got her hair dyed and she asked my sister is she liked it or not and she said yes and then he said y don't you trust me, and i said its like buying a dress you need more than 1 opinionatedd he said well i hope your not letting a 17 year old pick your dress, and i dyed my hair and wanted to show my mom and she was in her room and he said she was sleeping when i saw her 2 min before he said that and i got pissed!!!uh andd im still shaking and it was over an hour ago and i have to squeeze my arm and some nights it bleeds uh maybe somebody can kill him :) oh and me,my sister, and my grandma are thinking some thing is wrong because he only started being a douche bag after that got official engaged!!!