Diaper dilemma

So my LO is only 2 1/2 weeks, so far the pampers swaddlers cut into my babies legs and was leaving bad marks on her thighs. She is only 7 pounds and the diaper was still baggy on her. I'm certain the diaper wasn't too big. I put huggies in her for one night and now she has little bumps on her butt. Is this diaper rash? I'm starting to get so aggravated. The pampers didn't give her little pimple bumps at all but they were still cutting into her 😕 anyone have any tips or advice?