It's a bit difficult to answer your question without a bit more details. However, at least part of your question regarding fever and immunizations is a fairly common question.

Choosing whether or not to give a vaccine to a child depends on factors such as an immediate need to protect the child from illness, the child's underlying medical health condition(s), and the child's current medical condition. Fever with or without illness is considered a precaution (the doctor should think about whether or not to give the immunization during that office visit) versus a contraindication (the doctor should not give the immunization during that office visit).

As you probably know, fever can occur after many of the childhood immunizations and can be mild to severe in spectrum.

The severity of a fever is not entirely related to how high the fever is in a child but rather also depends on age of the child and symptoms that accompany fever.

I hope that I have helped you a bit. I suggest speaking with your child's primary care doctor further regarding your concerns since he/she has many more of the details in your child's case.