A bit tired right now, so this will be short.
Problems I have so far with the animation is that the body is completely static. It lacks a real sense of action that I think would be given off in a dashing animation, and what a 2 frame loop probably wouldn't provide without looking extremely jumpy. Only the legs and hands are moving, and even the hair doesn't seem to be affected by any sort of wind, which clashes with what little sense of movement you have. The sprite moving as a whole would seem the better option, more than bobbing up and down but rather left and right in addition. (Circular movement, put short.) Of course, there are a lot of subtle movements you probably don't really understand at this stage. Which I don't understand either. I don't know much about animation at the moment, still building on my fundamentals, so someone else may be of more help there.
Animation aside, the palette is bland and you seem to be relying on outlines and what looks like pillow-shading at this size to define shapes. And where's the light coming from? I don't see it. I know I posted
this tutorial
before but I think you'll benefit from reading it, as this piece (enemies count to some extent) and the piece in that thread actually share some similar problems, in terms of pixel tech.
Also note, if that's supposed to be a sword, it looks like a pole, and the little hero doesn't look very heroic. Edgy hairstyle, grey turtleneck and sweatpants of some sort? Man, all that gray is making me tired. Even in reality there's always a bit of color mixed into grays. Also of note, I am perplexed as to why s/he isn't wearing shoes especially considering the environment. Namely, the floor. Then again, do heroes like this really care?