I was playing on my friends Minecraft sever when suddenly my villager texture broke they don't look like the pink and black one though their textures were replaced with a Minecraft cat. And when ever I try to break a block with my fist the block looks like a Minecraft world I  have no idea if this is to do with the sever or something else.
I have not messed with the textures in any way as I have never downloaded a texture pack I'm just using default.