My baby turned 5 months yesterday. He had never spit up since birth. Probably like twice.

So 3 days ago, he started to bring back milk. Like throwing up. Sometimes it is like spit up. Sometimes pure fluid, other times like that solid spit up consistency.

This happens when he coughs, when he sits, and when he puts finger in mouth. He has had a flu and some cough for 4 days. Could this be the cause? Alone today, he spit up and threw up 3 times. That is too much for him given that in 4 months, he had spit up twice and that was due to someone carrying him and over moving him after a drink.

What I don't know is if he is gagging himself with his fingers. Or the mucus from the flu causing him to throw up. Someone told me that maybe he doesn't like my breast milk anymore. He is tired of the taste. Is this true?

Sorry long post.