DO your parents hit you for no reason??

I feel horrible today and i need to vent i hope that you don't mind. I don't know exactly what i did wrong this morning i was just brewing my coffee and i was joking with my parents that i wouldn't give them any and out of nowhere my mom calls me selfish. Is it wrong for me to joke like WTF? And then i went up to my dad and gave him the coffee and told him drink it before it gets cold and he was like "i don't want any!". I made one joke and now they call me selfish. No matter how much i tell them it's a joke they won't understand. My mom then comes up to me and hits me on my back and face and now i have no idea what to do. It's been 5 mins i have been crying. I'm sorry for wasting your time but i really need to vent it out. I really want to know what i did wrong.I'm not looking for pity tho.