Aw poor thing! I think its mostly because they can't hold their head up. Once they can do that and roll around they like tummy time a lot more! :)
My baby isnt crazy about it...but he sleeps on his tummy and sleeps so well that way!
Pick up that baby, so sad. Barrett has actually enjoyed tummy time and he is now starting to army crawl and rock on his hands and knees. So fun! But scary. I have to baby proof my place!