Vaccination Help! Advice urgently needed

Ok so my 18 month old is overdue for his shots and I can't bring myself to book him in - despite the letters from my gp and government telling me I must do so.

My doctor fobbed off both complaints/concern over my sons reaction to the vaccines (previous two lots) with no explanation or concern over his odd reaction.
For a week after his shots he would randomly go into uncontrollable fits of pure rage (only way to describe)
No temperature. Marks. Swelling. Just out of nowhe re and COMPLETLEY out of character would be unconsolably angry. Fists clenched. Teeth clenched. Screaming/growling . Hitting. Trying to head butt crib. It wasnt him. It was truly terrifying.
It would last 15 minutes sometimes more.

Now they want to reissue some of the shots on top of what is due now as they gave his first lot to early???
They rang yesyerday claming the government health dept has advised he needs more. I said I was not entirely comfortable with the vaccines in first place and need to think about how to proceed.
My husband is over it and wants to tell them to stick it up their ass. I am lost.
Food for thought please!

Was just mocked at dentist for wanting to remove nasty fillings- and they refused to d o it. So confidence little low