have you had any experiences of sensations arises from deep samadhi ?

If that someone just tell you that your experience of piti is the first indication of what to come, without actually knowing what that is nor experiencing it, then you will not understand it.

actually if u think enlightenment is a simple question, why u dont ask uncle google ?   

actually enlightenment can not be explain, only can be attained ...
eg like eat chilli, A like to eat chilli, he can eat 20 chilli n tarak rasa but B dont like chilli, B eat 2 chilli also started to cry ...
so if B tell A, chilli is the worst food on earth, what A will think ?
again if A tell B, chilli is the best food on earth, so what B will think ?
from here u can see both of them have different perception about chilli ....
if somebody explain enlightenment to u, he need to attained enlightenment first ... (eat chilli first)
and u need to be enlightenment too, to understand enlightenment ....(both also have eat the same chilli)
to totally understand enlightenment u need to understand sunyata/emptiness first ....
cos sunyata explain including the past, present n future (time) ...