Milk Protein Allergy - When Does Baby’s Pain Stop?

Hello:

Unfortunately, our near five month old officially has milk protein allergy: blood in stool, mucus poop, reflux, small feeds.

My question is: when does the pain for the baby stop? We have cut out dairy. About 4-5 days in.

We have not opted for the specialized formula just yet. So disappointing because our baby is very big and i would hate to imped his progress.