We've been following the Weissbluth method and it's worked well thus far. Our son has been STTN since 9 weeks from 7:00 - 6:30. The last couple of nights he's been waking at about 3am crying. I've gone in to give him a pacifier and he'll get more aggravated. I have sent my dh in with the pacifier and he gets angry. We then bottle feed and he seemed to calm and we put him back to the crib. He will then fall back asleep after 15mins.

Are we totally undoing the sleep training that we put into place? Is there a different approach to getting our son back to sleep? Or is this totally text book 4 month sleep regression?
TIA