Dairy, wheat, soy, eggs, peanuts, and fish Free diet?

My baby has severe food allergies but because she is only 2 months old and I feed I cant pinpoint what the problem is. My doctor wants me to stop feeding and give her formula but I dont want to. My lactation consultant told me to go on a dairy, wheat, soy, eggs, peanuts, and fish free diet. BUT... what do I eat then???? I dont even know where to start?