Congratulations on passing.
Best of luck with the future.
BTW at my first job after graduating I felt over my head, and the first few months were scary.
Pretty soon I got to know the people and they got to know me and I learned the systems and procedures and I started to relax.
After I passed my last exam I got the awful feeling that after cramming for exams I had no real new knowledge and I still felt the same as before I started.
When I started working however things came back and I found I understood things I didn't understand before... they seemed so obvious then.
The amusing thing is that after those first few months in your position... whatever it is, you will probably know your job better than anyone else in the company and suddenly you are the expert and people will start asking for your advice on what can or cannot be done.
The thing to remember during that period of fear in the first period is that after you are comfortable in your role... it starts to get boring and repetitive.
That was my experience anyway...