Anger Management help?

I am usually a very calm person. I keep myself calm by holding in most of my emotions but every few years I blow up. I don't know what to do. I blew up at only one person for years. The second time happened a few hours ago. My sister was drunk and told me to do something(every day she tells me to do something and pushes me around) so I told her to get it herself(respectfully) when I came back to my sister she told me she would throw up on me and I got mad and started to yell at her she yelled at me back and told me to grow some and that I was talking ****. That got me mad so I lunged at her but before I got to her I realized I might harm her so I stopped calmed down and tried to stop her from walking away by grabbing her arm but I kept my grip loose. That's when she hit me in the stomach and kicked me in the . When I jumped back in pain she started yelling that I tried to kill her. I am getting worried am I crazy?