this is something i see in most grows usually around 10 days after showing sex, as the initial flowers start to form the leaves will droop like they need water, but as they have been fed earlier today and are not as dark as i would like at this stage, to the point that one is starting to show a small amount of def that maybe not what appears to be going on, this to me appears as an indication that they maybe bored munching on Nitrogen and desire a change in menu, and that's what they will get, next feed bloom will be introduced, this should encourage the plants to put all their energy into bud production but keeping a background of half strength of grow nutes to take them through the stretch and beyond.