I read that the people who shouldn’t get vaccines are if they are allergic to an ingredient or auto-immune compromised.

When you’re baby is ready for the 2 month shots, how do you find out if they are allergic or AIC? Also when they are giving 6 shots at a time, how do you figure out which one it was? Do they do a test before to find out about any allergies or wait until a bad reaction? I was reading the side effects and I know the percentage is very very small, but what happens if you are in that small group?

Has anyone had this experience?