It's not necessary to stay always happy it is not possible. Everyone have their emotions when feelings. Feelings and emotions can change day by day every hour. You cannot expect same feeling from your body or from your surrounding. What you feel now is not same that you feel tomorrow or yesterday. The common feeling of happiness please only when you are addicted to something. Because the feeling of happiness is comes from pleasure in the pleasure is comes from dopamine chemical in our brain. That's why when we are addicted to something we can feel happy or pleasureble. Everyone has their life ups and downs. where up means happiest moments and down means saddest moment. When you feel happiest you have to laugh when you when you feel sad you have to cry because body needs every vitamin in same proportion otherwise you feel weakness. That's why we have to you feel happy as well as sad in bad moments.
thanks for reading this,
You can check out my other articles.