There is only one thing that anyone is scared of and that is the future. The past has gone, the present is now so technically that has gone so what you are afraid of is what is going to happen next.
Try to prepare for it.
Think of everyone as an equal, not a superior, but still show respect everyone.
Don't answer any question till you have thought out the answer.
Think of others as friends not adversaries.
People are intimidated by those in positions of authority but what you need to remember all the time is that they are just a person doing a job (obviously if they are an owner they are slightly different but still only a person).
If you are spoken to by a policeman you will feel intimidated even if not guilty so this is a good test and confidence booster, go and talk to a policeman! Just say Good morning, nice day, busy anything. You will find that as the instigator you will not feel scared or nervous.
When you go to the Doctor's knock the door and wait, when asked to walk in with confidence.
Start the conversation, Good morning Doctor, I have come to see you about.....
You may have noticed by now the technique, you instigate the conversation, don't wait for them to do so, you take the lead.
You will be surprised how the intimidation you usually feel will go away very quickly.
Hope this helps