Super Lemon Haze problem

I am having a slight issue with my newest plant. I tried to use the stickied subject to self-diagnose, but the photos would not show up for me. I am growing slh in my closet, cfl grow. Its close to it's 4th week and I've recently noticed that the lower most leaves have turned bright green with yellow mixed in. I thought it was the pH at first but the runoff is at 6.4 and the water im feeding it is at 6.5ish. I mix jacks classic 20-20-20 in for feeding. I had gotten conflicting answers previously with one person saying im under fertilizing it and another saying im over fertilizing. The plant is a very dark green. Ive attached some pictures. Thanks

When and how often do you water

You mite need to repot sound like rootbound to me good luck....

I water whenever the top layer of soil gets dry. Usually 2 days or so depending on how thirsty she is.