Cut the spike maybe a half an inch from the base, using very sharp and sterile shears. Sprinkle the cut with cinnamon. Then allow the plant to rest, and grow. It should be fine.
And if you take the spike into a vase with water, and changes this every day, the buds are likely to open, and the bloom can actually last a long time *s*
This way you will still have the flower, and the plant can recover its strenght.