So it's been 48 hours and fever is still there swelling hasn't gone away I tried massaging it but he won't let me he cried really bad. 😔 I think ER is our next step...

Swelling and fever, yes. Gently massage the injection site and it should go down. But definitely give baby some Tylenol.

yes give him some Tylenol, rub the spot where he got the shots, it gets swollen and hard when the medicine gets stuck in one spot, massage it and it will spread easier. and the vomiting could also be a cause from it

I would call in and see if they want him to get looked at.