Hai mama, aku totally faham lah, you're managing three little ones sambil pregnant lagi, dan dengan history preeclampsia tu memang ada pressure lebih. First thing: please reach out to your doctor or midwife about how you're feeling emotionally, they can support you properly, especially dengan health anxiety yang ada sekarang.
Honestly, few of my mum friends yang dalam situation sama cakap the guilt of "I should be calm for baby" tu paling berat, tapi pregancy hormones + toddler chaos = normal breakdown lah mama, bukan failure. One of them actually set very strict boundaries: some toys jadi off-limits during her pregnant months, tantrum times she just sat down dan breathe, tak layan drama (sounds cold tapi kids actually adapted). A few of us also realized messy house > stressed mama, so we literally let it go, or asked partner/family/maid untuk ambil that load off.
You're only in first trimester, long journey ahead yes, but break it into manageable chunks, not nine months sekaligus. Your emotional health is part of preventing preeclampsia lah, so self-protection bukan selfish.
You got this. Reach out to your support circle, mama friends, family, doctor, jangan tahan sorang-sorang.