Ahhh yes, totally normal lah, my first baby also macam tu, memang scary to watch but the doctor assured me it's just them learning to relax and pass stool properly since diorang kan 9 months dalam womb dengan anus closed. The key thing is as long as the poop consistency is soft and they're passing it regularly every day, the grunting and red face is fine even if it looks dramatic! A few of my mum friends were also worried their babies were constipated, but turns out it's just gravity working against them when they're lying down, so don't stress, watch the stool itself lah, bukan the straining