My 14 month old daughter started banging her head on the floor when she's mad?

Like I said above, when she is really mad or i tell her no, she screams and bangs her head on the floor several times in a row! Weather its carpet or tile floor, she does it hard. She also has started smacking in the face when shes in trouble, I've tried smacking her hands and telling her "we don't smack!" and spanked her butt and gave her time out in her crib, but it still hasn't made a bit of a difference. What do I do??