[koshatnik]

I had similar feelings when I started to use 'programmer' and 'developer' on my CV, and when I started my first IT contracting job. I had done programming in my previous job, but it was in no way acknowledged in my job description or grade. Similarly when I started to earn more than I had previously, I questioned whether I deserved it.

The chicken-and-egg situation with job experience and employability makes it inevitable that you will be in positions where you 'don't know what you're doing'. But if you have the determination to seek out answers and fill the gaps in your knowledge, you'll become that expert you think you aren't.