Baby Not Eating As Much

Hi ladies,

My little man is 9 weeks old and he’s been a really great eater- until yesterday. He will only way a couple of ounces at a time now. At night at 2 am and 5:30 he usually polished off a 4 ounce bottle completely dry and I was lucky to get two ounces into him. His 5 ounce morning bottle was 2.5 this morning. He has wet diapers and his disposition is the same but I’m just worried what would cause this? He’s really drooling a lot now, this is new and he refuses to sleep during the day. I’ve put in a call to his pedi but was wondering if anyone else was going through something similar. Picture because he’s adorable 🥰