Mercury spilled from thermometer due to purposely heating it up?

About ten years ago my curious mind might've caused a huge problem. I didn't really think of ask about it now but whenever it has comes up in my mind (handful of times) I shiver. So when I was about ten years old I purposely took a lighter and heated up the round circle at the bottom of a thermometer. I heard cracking and smoke came out, I don't think that much spilled. I threw it out immediately scared and I don't think I ever told my parents. Aside from the environmental dangers of improper disposal of the mercury causing environmental problems.. what effects and how serious were they to me? I mean I'm not insane or anything but what were the worse effects this could've caused me keeping in mind this was 10 years ago.