Uhm.

First of all, not too original to make a Fur Elise techno remix since there's a thousand others out there. But, as an electronic musician, I understand you're completely obliged to make both a Fur Elise remix as a well as a remix of Tetris at some point in your career. Haha.

Ok, so anyway, my thoughts on this song... it changes way too often. That might be fine if it tied together some how, but it doesn't. It just changes from one thing to another, to another, to another, and none of it blends well, none of it ties together, it sounds more like a demo song of everything that's on someone's CD; like previewing all the tracks. Everything in here by itself sounds good, but there's just no structure to this at all; it feels completely random.

I would suggest getting new hi-hats and also working on your drum mixing because the kick and hi-hat didn't mesh together well. This could be easily solved by adjusting the audio levels more. (Because that's what mixing means.)

I will give you props for making this loop almost flawlessly though. By that, I mean the ending just fades right into the beginning without stuttering or anything.

I really think you have a lot of potential from what I heard in this song, but just work on your structure and don't change up a song so often. The hardest thing to do when starting in music is to gain confidence in looping, because you don't want it to sound repetitive, but I suggest you start looping more until you're confident in it. Learn to make small changes along the way rather than have it constantly change into something completely new.