Every time I play Minecraft in Singleplayer when I break something, the block reappears, for example, when I break a Stone, the Stone reappears and when the break reappears again and after a while it disappears, and when I try to kill an animal or a mob I just hit after a while, for example, when I'm going to kill a sheep to get wool it only turns red after a while, so I have to wait a little bit until I can kill the animal or mob, for Why does that happen? because my internet is "bad"? or because I use a Laptop to play Minecraft?

Note: This does not happen in Multiplayer, also, i used Google Translate to post that.