Zara pucci-esque print top - size XS/small

Love this gorgeous top! It is tagged as a size small. I ended up getting a bigger size (because I love it so much and it was too tight across the back at the shoulders - failed the steering wheel test). I’m a US size 6. Armpit to armpit is 20” and shoulder seam to shoulder seam across the top of the back is under 16”. EUC.