You should always put more effort into your sprites than "some minutes". There's no point in posting them if they are not the result of real work but boredom.
Link's colors are to dark, and the shading is almost black. If you did the lineart yourself, then it's pretty nice though.
The sword is okay, but these colours could be brighter and different, too.
The blocks... well, nice. But make the center bigger, it's almost a pyramid.
House-tiles... with black lines? Remove these and they're a nice start.