Baby boy had his first shots on Monday. He’s 9weeks old.

He’s been super sleep(which I get) but his appetite was normal. Starting this early mornings feeding and 2 feeds after he hasn’t had a huge appetite. Not so fussy. But he had a huge poop last night after bath, it looked normal.

He also had a huge poop this afternoon which had small chunks of fat? They were white, there was also 2 small strands of mucus? And it was watery. He also spit up a lot after that feed. More than normal. (He doesn’t really spit up)

I also just fed him again and he seemed hungry and I think he’s still hungry (but he’s not fussy fussy it’s just a feeling) but when trying to feed him he kept latching and unlatching.

Is this just a reaction to the shots or could he be allergic to something?