Considering my father's gambling addiction, I never thought that I'd ever grow up to be a blackjack dealer. 
Wow. Interesting. The game is also called twenty-one, where on has to  compare card game between usually several players and a dealer
Nobody serious about the game calls it 21 though, except for maybe kids learning to count.
Since you are a dealer, you should already know that it's the most played casino banking game around the world. 
Yup.  In the dealer's course I took before starting work, that was one of the things that they told us the first day of class. 
Have you ever felt bad the days that you lost? since the objective of the game is for players to beat the dealer
Not at all! The casino owners know the game odds are in their favor, and when the players win, they're not winning my money, so it doesn't bother me one bit.
I am British but I know the rules in the united states is the dealer is also dealt two cards, normally one up (exposed) and one down (hidden). What's the rule where you come from? 
That's the same over here, although I am allowed to peek at my bottom card if an ace it the shown card.
valued as 11 is called "soft", meaning that the hand will not bust by taking an additional card; the value of the ace will become one to prevent the hand from exceeding 21. Otherwise, the hand is "hard".
Once all the players have completed their hands, it is the dealer’s turn. The dealer hand will not be completed if all players have either busted or received blackjacks. The dealer then reveals the hidden card and must hit until the cards total 17 or more points.
Blackjack
Blackjack is the American variant of a globally popular banking game known as Twenty-One, whose relatives include Pontoon and Vingt-et-Un. It is a comparing card game between one or more players and a dealer, where each player in turn competes against the dealer. Players do not compete against each other. It is played with one or more decks of 52 cards, and is the most widely played casino banking game in the world. The objective of the game is to beat the dealer in one