Is there a place I can exchange my diapers?

Ok so someone gave me three boxes of pampers diapers size 3...im due in about 8 weeks I need smaller diapers and I want nothing to do with pampers since they have that dry max in them. I know where she got the diapers from I dont want to go there she works there and she got them on clearance. I thought I remember hearing something about certain stores will let you exchange your diapers if unopened. Anyone know anything? I know someo of you will say dry max is whatever...but my daughter never got rashes EVER until I switched to dry max with her...then is was cracked dry raw horrible skin rashes...and so I now stay away from that brand.