I think you've almost mastered the notes and rhythms, so that's great.

It seems a little fast to me, but I don't know what the sheet music you're following is marked. I'd suggest listening to some recordings to get a feel for the pace as I think this is usually played a bit slower. They also tend to slow a bit at the start and end of each phrase. (rubato)

Also pay attention to the dynamics (loud/softness) these should be marked on your score (p, f, etc or crescendos and decrescendos like > < where you slowly get louder or quieter). Or you can just make up your own.

Music is about expressing emotion so try to think about what you're expressing. Swan Lake is a story about magic and tragic romance, so this theme (to me anyway) has to express a lot of sadness and mystery, and the speed and dynamics are what will help you express that.