This happened to me when I was about 9, when I didn't know what mercury was. There was a few droplets on the floor and I ended up poking it with my index finger for a few minutes. To this day I don't know what the medical effects were.
Unless you licked your finger afterwards, nothing.
Even if you lick your finger, if it is elemental mercury then probably nothing either. But don't try it!
Just curious: what would it need to be for it to do something? Not that I'm planning to...