Hello! First time grow, I am experiencing the same problem, I have a one week old White Widow plant and am giving it a solution of plant food with calcium/magnesium supplement growing in Coco fiber in a plant box that surrounds the plant with florecent bulbs. I try and keep the PH at 6-7 range in the water and plant food. I just fed it yesterday but I have noticed the drooping happen since before I fed it, from what I read it maybe too much water for the little seedling. Can anyone give advice on what I should do?