leaves twisted

Hi! This is my 2nd attempt at growing and I am terrified that I am doing something wrong, please help. Leaves are twisting,

9th week since planted indoors and 4th week of flowering and my one pant is really not looking good. I have three plants under a 600 watt digilux HPS bulb ,And an xtrasun air cooled hood I have had some heat issues but they have been corrected as of a couple of weeks after vegging .I vegged with...