He’s just so tired

My son is 4 days old. After a feeding in the early hours of the day he slept for a few hours and I needed to wake him to feed. Then he went back

Down no problem and I had to wake him to feed again. Then he had an appointment with the pediatrician(he had zero things they were worried about) and we came home and he was super fussy and wouldn’t let us put him down he just wanted to be held. He was pretty much inconsolable. We bathed him for the first time tonight and not long after that he fell asleep and I can’t even get him up to eat he’s so tired I even stripped him down to his diaper trying to get him to eat and he only ate very little in comparison to what he normally does. I’m just worried... I feel like something is wrong