If youre breastfeeding, start a food diary and see I'd there's a relationship between what you're eating and reflux. A lot of babies can't handle dairy. If its really bad your pediatrician can perscribe a anti reflux Med. My sons been on ramitidine since he was 7 weeks old and it has helped a lot.
Her Dr can give her a script to help. If you're breastfeeding try to cut down on your acid intake, cutting out yeast helps alot too. I give my daughter gripe water and it helps tremendously.
Are you breastfeeding or using formual? If bf it could be something you ate that messes with her tummy. If formula it could be the kind of formula you're using. I'd mention it to her pediatrician at the next visit though.