Shall I blame our luck or destiny if something bad happens to me?
Why do you want to blame? Tell me!
If something bad has happened, learn a lesson from it. Everything that has gone wrong has made you stronger, deeper somewhere. It has contributed to your personality, isn’t it? So be thankful, and move on.
See the past as destiny, future as freewill, and live in the present moment. This is intelligence.
If you do it the other way around, i.e. if you think the past was freewill and keep regretting it, and if you think the future is destiny and you are slack in your action then you will be miserable in the present moment.