Audio speed up

I'm not a very good piano player, so I recorded something at a slow tempo thinking that I could just speed it up using the speed controls in DR. When I tried it, there were all kinds of strange sounds that it created making it totally unusable. Is there any way to get rid of the strange sounds, in order to make a speed change usable?

I tried to upload the music file so you could listen to it, but I got the message that you can't upload MP3 files. What types of files can you upload?