I have some ak47 plants vegging, 2-3 of them are droopy as hell, look close to under watered but that's not it. It is around 65F in there most of the day and around 60F at night, would this cause some pheno's to droop?
Possibly, If you could keep it a bit warmer it sure would'nt hurt. But Also remember AK47 is a sativa. I have one about two weeks into flower and she always looks droopy. Not the stems but the leaf blades themselves. As long as she is growing and has good color I think you will be fine.