It stoped growing fast as at the beggining. I hope it gets to a nice size before flowering begins. These lights are really weak, I need to get stronger ones as soon as I'm going to have money for them.
You need to up the dossage on your nutes bro. Yellow leaves mean you don't have enough nutrients in the soil. Your plant looks ok for the size light you have. I wouldn't give up but maybe try an LED light instead. Good luck fam👍🏾