Last year my sister gave me her amaryllis post-flowering with droopy leaves as well. I just treated it like my others and the new leaves came in green and perky. The problem was most likely lack of light. They do like lots of sunshine when they're storing up energy for the next flowering. There is a chance that the bulb may skip a year in flowering when it's been stressed, but it seems that yours will be fine since you got it long before the dormancy period. Eve