My daughter does the same thing! Drives me crazy! She cries when I put anything over her head and flips on her belly anytime I change her diaper. There for a minute, I was holding her down, then I tried to put her diaper on while she was on her belly (not easy!), finally, I've started communicating with her. Amazingly I THINK it's working! I've really tried more and more to tell her what is going on and she is responding positively. ok, so when I go to put her shirt on, I'll tell her what I'm doing and look through the hole in the shirt and make faces. Then I'll count to 3 and slip it over her head. She still gets whiny when I put her arms through, but I do it real quick and then talk to her again about how good she did and it's all over! YAY! Then with the diaper, I say, "Ok, baby girl, mama's going to change your diaper- you ready? you gonna be a good girl?" From that point forward it's one word commands: either Stay, stay, stay, stay or hold, hold, hold. I started doing this to put her to bed too and it's worked the last few nights. "You ready to go night night? ok, I love you very much and now it's time for Ta-Ta to go night-night." I lay her down and she gets comfy. I'm sure I've jinxed myself now, but hopefully this will help some. Good luck!!