Little help please

Hey everyone,
Well i dont know if i neccessarily have a problem or not, it more of a question. Im new to growin so i dont have much to gauge growth on. This is a picture of my baby. Shes a strain of Northen Light. My question is shes 5 weeks producing her 6 set of leaves but still is pretty short. So am I doin anything wrong? Shes under flourecents for now till the HPS comes. Been keepin the rh at like 45-55% and temp between 70-78. The ph is good as well. She looks healthly so maybe im over concerned but like i said shes my baby. So any help would be very much appreciated. Thanks again

P.S. ( I know its early to tell sex but she was feminized so im a little confident)