Throwing up

babybologna2012

My LO is ebf and has been crying for the past two days but only during the day after she eats. Also last night wheni tried to give her the vitamn d drop she threw up quite a bit and today she did the same. Anyone have an idea of what itcould be? I think she has a dairy allergy but i havent had any but I'm thinking i need to have a stricter diet completely dairy free