When do babies digestive system mature? 11 week old screams when gas/poop

Hi Everyone

When does the digestive system mature a little bit in newborns.

My just turned 11 week old screams and grunts really loud for around 5-10 mins. No consoling can really help. Lord forbid I try and LO on their back during that time.

After LO calms down, there is usually a big poop about 10-15 mins later and all is well.

So it's definitely gas and the poop going through the system. I feel bad during it cause you can tell the pain. I'm like " you can do it, push! " lol

When does that get better?