She's a beaut! Very well executed, looks like an original water-colour. Must say I have always loved Art Nouveau too, mainly from an architectural perspective, but you've done the art justice here, nice work!
You know, this really reminds me of 'Gather Ye Rosebuds While Ye May' by John William Waterhouse ([link]). Something is similar in the stained glass of Waterhouse's painting and the floral pattern in the background of yours; in the face surrounded by blossoms; in the draped clothing.