Aww mama, 1 month tu mmg challenging especially with colic! Domperidone is generally okay untuk breastfeeding, it's one of the safer options, tapi memang best check with your gynae or paediatrician pasal dosage & side effects specifically for baby. A few of my mum friends used it & it helped, tapi timing matters (some said kena makan dulu before feeding sessions). Besides the ubat, try power pumping or frequent feeds (even 2-3 hourly) to stimulate more supply, susu tu based on demand, so the more the baby draws out, the more you produce lah. One of us juga added in latching support (check if baby's latch is deep enough, sebab sometimes baby tak hisap betul & susu jadi nampak kurang). Make sure you're eating well, drinking lots, & getting rest when you can, postpartum exhaustion mmg sabotage supply. The colic + not sleeping at night tu separate issue but can also make feeding harder lah. Do chat with your KK nurse or lactation consultant about the latch & positioning too, boleh jadi that's part of why baby's frustrated. You're doing great at 1 month, this phase is really tough!