Is it possible to be breastfeeding and have baby be getting “enough” as far as volume but not getting enough nutrients?

Here’s my situation/why I ask.

My son is 3 months old and has been breastfed and bottle fed (with pumped breast milk) from the start. I keep track and he consistently eats 20-25 ounces a day.

The last week his sleep has plummeted, he’s gone from waking once at night to feed and then going right back to sleep, to waking every 2ish hours to feed, and crying a ton when we put him down.

He also went from pooping about 6 times a day to pooping maybe once or twice a day and it’s super runny when before it was mushy.

I also just weighed him at home and according to my scale he weighs the same as he did at his last checkup a month ago 😫

My milk supply hasn’t dropped and it still has plenty of fat in it (I can see when it separates in the fridge).