Aduh, this sounds stressful especially bila firstborn kan! Honestly, lendir dalam najis baby dan frequent pooping 5+ times sehari boleh normal untuk babies on formula, tapi kalau suddenly berubah dari biasa dia, better check with your paediatrician just to rule out any tummy issues atau if there's a sensitivity, a few of my mum friends experienced similar and turned out some babies just need a different formula or sometimes it's just a phase. Kalau dia lively, gaining weight okay, dan nappy wet enough, usually it's fine, tapi since he's only 1-2 months lagi, these early weeks boleh jadi sensitive so best to get expert eyes on him rather than guess-guess, terutama if the change is quite sudden. How's his weight gain and mood overall?