hello hunny, i have had the opposite, i had straping on for first 3days but could stand it and was causing a rash, so wore a sorts bra for last 3days and its got baggy!!!! i would think is just because of the swelling, but ask your nurse on1week post op check…… if it becomes too tight then get another size……. one back size bigger then normal, and one cup size bigger then expected to be, thats what i did. x x