Why am I afraid to be happy?

I dunno why, I just cun let myself be too happy during the trip. I dunno wats holding me back to be happy.
Is it because if I am too happy now, I will be very upset the very next moment.
I hate the feeling of pain, pain in the heart is unbearable. Thats y i dare not be too happy??
Let go...is it so difficult to let go? Even till now??
Have I have a serious thought of my future?
Wat do I want to achieve in 5 years time? Where will I be by then? Wat are my plans?
I dun wish to think, I hate to think, I am lazy to think. Can I not think?