leaves curling, check out the pictures..

Ok this is just over 2 weeks old. I have 4 critical kush and 2 have the curling leaves. When they grew 5 nodes I tried main lining.. Which is topping at the 3rd node toand trimming anything below to get 2 equal mains which topped again will become 4 and eventually 8. I think this curling could have been caused by the main lining/ topping but I'm not 100% sure.. If anyone has any idea why they are curling and if it's a problem I would really appreciate it. Thanks

Hey dude the main lining wouldn't have done it their probably either over/under watered, or the light is a bit close