Hi Bigmike - Some good tips in here.
I would get a toothpick or chop a straw in half, moisten the coco a little so you can push it down by the stem and attach it with a sandwich bag tie.
It probably stetched a little becuase of the light being too high or not powerful enough - in future, you can build up the young stem strenght by having a fan gently blowing across it from when it pops it's head. Just a gently rocking for birth will strengthen it. Once the roots are put down and the stem has grown a little, it shouldnt be problem.
I always keep a movement fan on - not only does it strenghthen the stems, but later on in the grow, keeps my buds from molding.
Happy growing!
All the best
Blue ^_^
I agree with the fan is a must! But about the support, dont you think is already tall enough to just support it with stick rather to buried it? Am not an expert ofc, actualy i am a beginner but i studied enought and have worked with garden generally besides cannabis