Usually at 4 months they go through sleep regression! Happens everytime they learn something new (rolling over)! It lasts no longer then 2 weeks
Does sound like it could be regression, or general development related with the want for extra milk - as annoying as it sounds, it’s probably a ride it out situation. Length of time it’ll last varies between babies but the best thing to do is stick to evening and morning routines as standard. Does she have access to her hands to self soothe? Screaming when being put to bed might be overtiredness or trying too early? Could try and shift that by 15 mins at a time and see if it makes a difference. It’s always something with these babies 😅
Loads happening around 4 months in regards to their body clock and sleep hormones so could be that :) https://www.instagram.com/p/C_P36tYBPcj/?igsh=MWg1MGJ6NHhwYjJyeA==
4 months is a big development point for them, they’ve just realised you are not a part of them and they can be separated from you. Imagine you woke up without your arms, you’d freak out as you assumed they would just be there! Honestly, after two babies doing the exact same, you just have to ride it out. Consistency is key, and they will get better with time. I guess one thing I found is they needed the sensory input, so holding them close and rocking quite firmly. When I put them in the cot, I would keep my hands on them quite firmly until they were settled - pay attention to how firmly you hug them and try and use a similar pressure. Honestly though, from 4 months, both my babies would wake regularly until about 12 months, when it reduced. My eldest only slept through nearer 2 years old, and my youngest is 14 months and still wakes 1-2 times. I guess what I’m saying, is this is pretty normal behaviour, so take the pressure off of yourself for trying to fix it.
Do you have a nighttime routine for her? And do you swaddle her? She could possibly be going through a sleep regression