OP I am sorry to hear that you have to go through this, by the sounds of things, on a regular basis. You sound like you aren't old enough to have a dollar to your name or have the capacity to fathom a life outside of your parents care. Your dad has seen more years on this planet than you have, for now you have to make sure you take care of yourself first. As he could physically harm you more.

Please know that the world is not like this at all. It can be a beautiful thing, much more than what you dad is. There is a dark side to this world as well, and I am sorry that you have to experience that horrible side for the duration of what sounds like your childhood. I am proud of you standing up for yourself and wanting to protect your mum, not many people have the courage to. But with the nature that your dad is, and your physical size in comparison, there is a time to fight, and there is a time to submit. Please keep that in mind, or else you may escalate a situation into something worse than it could've been. Although for this one, I think you handled it well. Trying to defuse the situation without needing to resort to violence. Luckily, your mum was there before your dad could make it worse.

And when you are able to afford to separate yourself from your dad, life can be so much better. There are caring people out there. I wish you the best. Good luck.