I got first class degree in CS, but I know nothing about computers

I am programmer and I have been doing it since 14 years old. I believe I am great at it. I've just finished my CS degree in pretty good rated UK university. But I feel that I know nothing about computers except programming and little bit of maths. Is it my fault that I learnt stuff just before exams to pass it and forgot everything afterwards? Did I really need to go to Uni? What do you think?