I have had many happy moments in my life, one of them was when I gave my dog. It was a black cocker, was 3 months and I remember the first day, It never stopped running and playing with me. But all good things come to an end, and that was when my dog died 2 years ago. It was the saddest day of my life.
I have had anothers happy moments, for example when I buy my new car and I drove for the first time, when I win a ham 5 jacks "pata negra" and a bike in a tombola,... In life there are a lot of happy moments and you should enjoy to the fullest.
To finish, I write my two favorite songs that talk about happiness:
Don't worry be happy - Bobby McFerrin
Happy together - The Turtles