Is this Nute Burn or Light stress? (hoping light stress)

Hi! In my experience light stress looks a little different. The leaves might start to droop and the green healthy color starts to fade to lighter green in the top parts where the light intensity is the strongest but I don't think it will make the tiof of the leaves yellow only. So i'd say it is something else but you should not be worried 'cos she's still young and fragile but I'm sure she will grow out of it if you just give her time and keep growing her like you used to!