Its a really hard call, but from what you've said it sounds like Matthew could have a kind of reflux called the "happy chucker" LOL I think its the mother's group name LOL...
Anyway its worth discussing with your GP or your early childcare nurse, especially if he is having no weight gain or slower weight gain and is acting painful.
Matilda didn't vomit as much, but would scream for hours and thats how we found out her little throat was burned, it sounds like Matthew is more like Felix who was a happy chucker early on. I would check at the 2 month vaccinations if he doesn't seem too painful, otherwise with the nurse earlier... HTH!
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