K.A.
exchange and get te larger size. have it altered to fit the size you are while in a arms out in front shoulder height. During the wedding you will be doing a lot a moving , huging people with both hand and pulling the dress up and forward. You will be dancing too. You want to be 100% confortable moving about during the wedding, and have fun. ( not giveing it a second about your dress. A dress that look tight could be noticable, & does not look great. You want to look great and comfortable. Get the larger size today, ASAP
I helped my daughter get a dress for her wedding. It needs to be comfortable. As you loos more weight the last week it will add confort
Kay F