

any event which affect one of twins has 50 per cent situation to happen with them
I don't understand what that means. For example, if I were to punch one of a pair of identical twins, the twin that I punched would feel the pain, and the twin that I did not punch would not feel any pain. In this regard, the two twins would have no more of a shared consciousness than would two strangers.
I suspect that if someone were non-destructively copied, the situation would be similar, as mwengler suggests. The two would have a common set of memories up until the point that the copy was made, but from that point on they would have no common or shared consciousness; they would be two distinct people (albeit with an uncanny resemblance to each other).
It means the following in your example:
Suppose I am one of twins, but I don't know which twin I am. But I know that twin 1 will be hit in face in next 1 minute. In this case I am in the situation of so called indexical uncertainty and my best guess is that I have 50 per cent probability of being twin 1 and thus 50 per cent probability being hit in the future. After I will be hit, I will know with 100 per cent probability that I am twin 1.
In general there is problem with the idea of copies, as it mixes several different ideas and it results into paradoxes. ...