Milk intake decreased

N.

I’m really confused. My little one is 4.5 months old and he has both expressed bm and formula. He used to drink 3 hourly 90-120ml then recently it started stretching to 4 hourly but the amount is the same. Sometimes he drinks about 25oz a day sometimes more and today it hasn’t even crossed 20oz.

He doesn’t cry cause he’s hungry he’s infact a happy kid on the whole. Last few days he’s been crying when u try to feed him 3 hourly cause I’m stressed he’s not drinking enough. He’s growing well and I think he has enough wet diapers. What are signs of dehydration? Like he’s alert happy excited. Just been making more grunting noises and drools more so thinking teething?

I don’t know. Advice? Should I see a doctor? Or give it a few more days?

And also he drinks at night like 6oz before sleeping and sleeps for 5 hours. Which is really good so infact now he fusses when I give him milk I’m just really confused.

And he drinks the best when he’s sleeping or napping. When he’s awake he’s super distracted and doesn’t drink. I don’t know if I’m making any sense here. Haha I hope someone gets me!