Alright for a first entry. Work on your game development skills and I think you can really make something great.

Just some suggestions on this game:
-Have the direction key in the actual game. (People forget easily.)
-Add some sounds (That is easy in Java.)

Anyway! Nice job!

The concept of not seeing my character is interesting but also kinda difficult ;)

This was a bizarre game, in a way. It was simple, but was enjoyable. The trouble with simplicity is that it can get monotonous really quickly. If there had been just a bit more variety I would have enjoyed it more than I did already. As it is it was excellent for a first LD. Good job on that. I'm sure as you get more experience with game development your Ludum Dare games will become very cool.

Nice job! Am I hearing music created with FL Studio? :D

Yep!

This game was really confusing, but you can easily get better though practice!

High-five for first Ludum Dare! Me too!
That said, this mostly seems like practice coding? Keep making these small things and you will gradually get better!
I'm digging the music!