Pretty nice simple runner with no chaff! I think the biggest feedback i'd have is if you're looking for more coherency with the art style i'd avoid mixing different pixel resolutions. I aint the pixel police though, look for the style that you enjoy making the most. 

Got 6368 score. I like the background art, it's very well done; Nice dithering effect and colors. The game is too simple for my taste but still pretty fun.