There are so few games where every single asset was made by the game creator, so I really want to commend you for that. I though the 'Aesthetics' or the look/feel of your game was really excellent, and its impressive that you pulled that off with no help, so really well done on that. I also really like the way you laid out the levels because I believe its quite difficult to really understand good level design, and you seem to have a knack for it. There is a lot of scope for you to continue to develop off of these existing skills and create even better experiences, so keep going, and great job.
PS) I also really seem to enjoy creating 2D platformers, for whatever reason.