Leaves folding in

Im guessing your soil is too hot. Depending what you planted it in, and what ur using to water it with, Ive noticed my leaves do this after a strong feeding regardless of plants age. If your using nutes- stop, f not then depending on what you used to pot it up in, it may just have too many nutes in it available to plant now. if you water it a bit less often, plants need the water to absorb nutes thru, so less water can mean its taking up slightly less nutes...but thats a minor fix. U could try letting the soil dry out quite a bit and then flush 2X the volume of the pots worth of water thru to take out some of the nutes, but personally its pretty minor so Id just water less often and keep an eye on it for another week, Dont use any nutes on it for at least 10 days of so ok. And some strains seem to have very narrow leaves like this if nute levels are even in the normal range- a decent half strength feeding on my zkittlez would make her newest leaves go like this for 3 or 4 days. As long as the tips are not yellowing/burning your still in normal range.