That's how I felt when we went there (with six kids).
We walked in the building and there was a Sistine Chapel sign with an arrow indicating the way to go. I thought that meant the entrance was just around the corner. Wrong! An hour and a half later we finally escape the labyrinth leading up to it, and I really had to fight the urge to take a quick look and get out the door to freedom as fast as we could.
It was beautiful, I'm glad we saw it, but it was not a particularly enjoyable experience at the time. It was more of an endurance test.