Doing it's thing. This is where I started to notice it cupping on the upper leaves. It has been like this pretty much the entire time, I have another plant in my tent that's decently shorter than this so I wanted to keep the light low enough for both, eventually I got two and got it situated. live and learn.
Looking at your cupping in flower they look like they drastically need water. If you're only giving it 1 nutrient, it probably needs more food too. Try Athena if you're looking for an easy 2 part solution.