i was BFing and couldnt anymore because he stopped lactching on so i'm pumping but have sore nipples and want to switch to formula now b/c i will be returning to school and work soon as well. but my question is i introdued formula incorrectly and now he is super fussy, his never calm inless his sleeping and now wakes up every 2 hrs he wasnt like that while i was BFing so i think its the formula. my boyfriend says to just BF for a few days and then start mixing in the formula and start re-introducing, should i just mix in now or BF for a few days cause it will just mess his tummy up even more? i was feeding him similac- advance and he is 1 month old.