Bests & Worsts Reviews from Amazon

So I have a full drawer full of Lane Bryant/Cacique panties in 26/28, and have been buying them for almost my whole adult life and was just hoping for something with a little less $ outlay and that possibly lasted longer. The waist/hip measures on those on the website is Waist: 48-50 and Low Hip: 56-58, so I bought these in 13, because the size chart said hip: 56-59. But OMG these are giant. Way to make a fat girl feel like an elephant. I obviously can't wear these. I gave it 2 stars as they appear to be relatively good quality (soft cotton, nice waistband, no sketchy sewing/seams that I detected) so I may try in a couple sizes down to see. Anybody know if I can exchange these? 9 pairs are still in the package - one pair was pulled out to inspect and take the photo, but I clearly haven't worn them.