Leafs problem

yup yellow leafs they are so mr green fingers lets get this sorted first if this leaf was taken from the bottom of the plant im pretty sure its a nitrogen deficiency whichh would also explain the browing too if shes not getting enough N she will have trouble uptaking her Cal mag which looks like this just up your grow feed and keep eye on it she should eat up the yellow leaves they will drop off and then she should replace them with fresh set of nice green fans :) Best of luck anyway bro im sure youll be fine :)