2 weeks into veg...3-600w hps grow

they will be 2 weeks tomarow from harborside... i had almost lost 3 because of fresh air being so cold , the stems turned all purple and all the leaves were pointing down, i moved the air and they were all standing fine after they slept for 6 hours, now im wondering how they might turn out or not?? any one done this before

theyll be fine but if you have such an area you really should be using MH lights while they are in veg or youll get stringy lanky plants