There is actually a name for this phenomenon, can't think of it.. but it quite literally goes exactly how you described it.. the more you understand, the more you realize what else is out there that you dont understand.
I believe Einstein had a great quote about this too.. im certainly not going to waste time looking it up, but the point is..
you learned more, and you know more than you did a week ago, thats a fact, you cannot change that fact, unless you lesioned your mammillary bodies somewhere along the way this week. Its just a false sense of insecurity because with this increased knowledge you've just opened up more routes to details that you never knew existed before.
It is IMPOSSIBLE to know everything, but its damn sure a guarantee that you are better now than you were before. Take it to the bank