CMPA or lactose overload

[Mountainview8]

I'm wondering if anyone had any advice/experience with CMPA or lactose overload in a breastfed newborn

My 4 week old has started having green bits and mucus in his poo, it almost looks like bits of spinach. His breathing is a bit wheezy after feeding, seems quite uncomfortable with wind, has reflux, spots and a bit of cradle cap is appearing. Generally he seems well and doesn't cry much.

I'm wondering whether to try cutting out dairy or if it's more likely to be lactose overload. I think I do have quite a strong let down and have been leaking quite a bit the last few days.

The symptoms of so many things overlap.
Given the wheeze after feeding I think I would do a trial of dairy and soya free and see if that improves things.
There are also leaned back positions that can help with fast letdowns or hand expressing into a muslin before starting a feed

Ours had the symptoms you describe (Welsh health visitor likened nappies to laverbread) but also colic, wouldn't sleep, screamed when not feeding. It turned out to be CMPA and soya allergy but we didn't work it out for a long time.