15 days small plant. Dont grow

That keen eye, lol hold onto it. It's good that you're seeing these little things, but I wouldn't worry so much on the growth but color and worrying about nutrients and what not. Your girl is good for now bro 👍 you'll notice when something is wrong 👌👊🤘

Thanks to all. And one more question: this plant have 5 leafs on top is it normal or mutation?

It is a little short, but for 2 weeks it looks fine. When it's not growing up, it's growing down, there are roots too. Your girl is healthy, watch a time-lapse of weed growing and you'll get a better understanding of the leaves movement, also if you want a tall plant, raise your light. 🤘👊👍

May be a runt. It could possibly be forming its roots to take off soon. I would make sure your ph is in range. Looks healthy for most part. Would give it more time. More light if you can. Good luck and happy growing 🌲🌲🌲👊