Grunting Straining all day and night!!

So my LO is 4 weeks old now and since we brought him home he has grunted and strained. He is doing it all day long and even waking himself from sleeping. When he wakes, he is screeching in pain. He isn’t doing it to pass gas or to have BM because he passes gas just fine and doesn’t produce a BM from the grunting. He is straining so hard and long that he turns from red to purple. His eyes even look like they have broken blood vessels in them. A lot of the times when he starts this he wants to nurse too. We have diagnosed him with reflux and initially started on Zantac, which didn’t work and now we are on Pepcid which I am seeing little improvement with. I have also eliminated all dairy and went to almond milk. Maybe it hasn’t been long enough for that to completely work its way out. I am almost certain he might have MSPI since when I did eat dairy his BMs turned green. The pediatrician mentioned grunting baby syndrome, but I am not convinced on that one 🙂

So, my question is….did anyone else’s baby do this? Does it ever stop? What did you do to soothe your infant?