Fun photo. It makes me smile. She looks like she is indeed celebrating. If you had caught both of her feet off the ground I think it would have an even greater impact.
wish i could see that other foot! if she was suspended in air, that would have been a cool touch for this shot. like the happy go lucky feel, and the color of the sweatshirt with the jeans.
I think a different background would have worked better. I also think you should have backed up (zoomed out) a little so that her right foot would be included.