You just wanted to say that you are Twilight Sparkle. You just wanted to have this awesome power and nice, purple body for some time. Week or two, who knows. But it turns out that you had some other desires, too. Transgender desires. You want to look at your purple body in the mirror and admire it. But it’s perfectly fine. Celestia and other ponies will accept this desire, and Twilight likes you so much that you will be able to spend quite a long time in her nice body.
 
But right now, you can’t stop feeling this…nice sensation. Is it perhaps because you are wearing this pretty dress, honey?