My zucchini flowers died before they opened up for pollination?

Trying to grow zucchinis in my apartment where the balcony allows enough sunlight coming in. The plant was fine and it started flowering a bit later, but two flowers were able to reach to certain size then they died before they could open up for pollination.... Just don't know why. Does it need more fertilization? I water it everyday and it faces the sun in a room temperature.. Please help