DIDK Women's Sleeveless A Line Fit and Flare Glitter Above Knee Party Cocktail Skater Dress

I'm 5' 5", 135lb, 27.5 waist 31" bust (smaller on top) and wear a size 4 jean. i wear a small and sometimes and xs in dresses. what size should i get?

Is the glitter uncomfortable?

Why under material does it say zipper, material is cotton, polyester, rayon and the percentage of each, so can you please be specific info?

Wash instructions? Was it wrinkled in the package once opened? Can it be ironed or steamed?