Pratik, although the hermaphrodite flowers are perfect in that they have both male and female reproductive systems within the flower, "under certain conditions its flower morphology is unstable and subject to “sex reversal.” ... "High temperature and water stress can lead to a shift toward maleness, in the form of a reduction in the number of carpels (normally five) comprising the fruit. " Read more here:
http://www.ctahr.hawaii.edu/oc...
When my tree started developing flowers, either the buds dropped off or the opened flowers dried up and fell off. It was nearly two months before fruit was finally borne. We had a drought and record-breaking high temperatures during the months before (May and June) so the flowers were unstable.
I am guessing that your temperatures had been quite high recently. So be patient, your tree should be coming around soon.