Pinching, Hitting, and Kicking

[mamamac]

That's all we do now during diaper changes. We sing songs, distract her with a toy, but she will NOT STOP!! It's kind of embarrassing that my 15 month old is beating me up. I have bruises up and down my arm from her. I have yelled "Ouch!" like it really hurt-makes her laugh, I have grabbed her hands and told her "That hurts Mommy, we don't pinch"-she laughs again, I have sort of pinched her back (she has no loose skin, so it can't hurt)-she laughs, I have tapped her on the butt-she laughs, I have picked her up and set her on the floor and very firmly said "No pinching" and walked away-she sits there and smiles at me or calls my name. She does this with my husband as well. Sometimes she stops pinching but then starts kicking and I mean kicking! Its not like she's just kicking her legs up and down, it is clearly directed at me. This seems to only occur at changing time, she doesn't do it while we're playing or anything, at least not yet. Any suggestions?! What about any good dicipline books for toddlers? Thanks!