Certified GKH Gardening Expert
There are two separate flowers. Male, and female. Usually, the males will show long before female so that there will be pollen around. Females will show up, and have a small fruit on the bottom. Once they are pollinated they will swell into fruit.
Most of the time, this takes patience. Sometimes, if it is hot and dry out, then it will take a lot longer before you see female flowers. Once it is cool, and a little more humid, they will show up.