Ok so I have played the 3 levels you uploaded, very quick review:
Game felt smooth, i didnt notice any bug.
Graphs were good, all the assets were done in the same vein so no patchwork of styles.
If those are supposed to be the starting levels the level design is quite awful, and if its not its still pretty bad. Most of the deaths are due to things you cant avoid/couldnt foresee. So you have to die one time on almost every obstacle to progress, and thats not really good design. Overall your level design and a few elements of your gameplay could be so much better.
How am i supposed to know which key to press to fire? Its not written in the tutorial.
The sound design in general gets tiring really fast, i cant give you much advice as its also not my forte.