Milk Protein Allergy

My 1-mo-old daughter is EBF has recently had some frequent explosive diarrhea, and one time it even had blood in it. Her pediatrician said it could be a fissure or it could be a milk-protein allergy. In order to figure it out if it is a milk protein allergy, I myself must abstain from dairy for the next 3 weeks, which will probably be the hardest 3 weeks of my life.

I’m wondering if any parents have experience with a milk protein allergy? Did your child grow out of it? Do they have any other food intolerances?