It's impossible to to answer your questions, since it's unknown which compound of mercury you possess
The fact that you're asking such basic questions belies your statements concerning your knowledge of inorganic chemistry, it's rather likely you have an amalgam, which means that the mercury is bonded to another metal, such as sodium or potassium
Alkali metals are quite hazardous, generally alkaline earth metals aren't quite as dangerous, you need to study a lot more applicable chemistry before you injure yourself or others
You can find out a lot of information by using the search engine, so hop to it