Do chewable vitamins do anything if you eat a lot of them?

This is probably a stupid question and you're probably looking at me as if I'm a low life druggie trying to find a new high, but I'm not. When I was younger ( at some point between 2nd-4th grade) I ate about 12 vitamins because I wanted to see what would happen. All I remember was that I wasn't able to get to sleep and I had a stomach ache.