Lovely dress but I got it in S, it doesnt stretch AT ALL so I shouldve got M

I really looked forward to wearing this dress but it dint fit. It was way too tight and i m suprised because all my fashion nova dresses are in size small, including the denim dress i bought alongside which was a perfect fit. And by the time i checked to order for the medium, it was already sold out. I cant return it according to the policy which is sad so its jst lying in my closet.