Sexual Harassment or normal?

My mother touches me. Like she touches in a playful way, or straight up touches me. And I don't like it, but if I say I'm uncomfortable she'll use that stupid "but I'm your mother" excuse. And she keeps doing it when I clearly show my face of uncomfortableness. She gropes and slaps my ass, then she feels around my boobs, sometimes touch my vagina, and tells me to get dress in front of her still, and i'm a about to be 16. Is this sexual harassment or not, and if so how do I tell her to stop without getting hurt?