help please!! 2 month shots and no appetite

My baby had his 2 month shots on Monday and has been acting different all week. He slept a lot right after the shots and has been fussy especially during feedings. He will seem like he's starving and have trouble feeding .. both from the breast and breastmilk in a bottle. Today (Wednesday/Thursday- 3 days after the shots) he has been refusing his last three feedings.. constantly pushing off and barely eating. He also has been pooping a lot in the last 24 hours. Also I've noticed he is developing a wet cough. Is this normal after shots?! I'm extremely worried that he's not eating.