leaves are look burnt

[busta318]

can someone please help! i have just started to flower my 2 plants and they are looking sick.......the leaves are starting to curl under mainly at the top and the top leaves are going brown from the tips. the lights not to close... can some help..

the plants are at around 10weeks old and there in soil, the light is about 70cm above the plant so i don't think there getting burnt from the light........
i think i might of over fertilized then......