Your daughter could well be reacting to cows milk in your diet. Give it a couple of weeks, and see how she goes. Babies aren't allergic to their mom's breast milk, but they can definitely be sensitive to something mom is eating!
This happened to me when I was a baby - I was allergic to the cow's milk my mom was drinking. Her doctor told her to stop breastfeeding me, and start giving me rice cereal and soy formula! So she did, and I cleared up....shame she didn't realize all she had to do was stop drinking milk (which she didnt' like anyway).
Hope this helps.