Yesterday i had gotten to work when the baby sitter called me to tell me she was almost out of BM and could i run more to them. I was unable to do this and so they supplemented with 1/2 BM 1/2 Formula that they had to make it through the day. Is this going to upset my baby? he is back on full BM today and i am worried that the slight input for one day is really going to mess his system up! Is there anything i can do to make sure that doesnt happen? is it too late and i just have to deal with it?