Leaves curling, drooping, and turning yellow...help please

Hey Guys,
New here to the forums, and I have looked around to see if the was any specific threads that could solve my problem, but none seemed to fit what is wrong with my plant. As the thread title stated, my leaves are turning yellow, drooping, and a few on top are curling. A little info on the setup I have going: Plant transported from a half gallon gardening pot to a 5 gallon pot 4 days ago. Using foxfarm ocean forest and happy frog for soil. Have a single 600 watt hps grow light which is 2 feet above plants. Temperature is 78*. Have watered twice since transplanted, and the soil feels moist. Is this simply stress from transplanting, or something else? Pics are attached, please let me know what you think!

could be heat or Mg, i would flush them asap w/ 6.5 ph... r u testing your waters ph?? this could be a problem too.. could be locked up. flush w/ a 6.5 ph and you should be good to go n a cpl days..

This is my first grow, so I am not completly farmiliar of how to raise my ph. I am using distilled water, so I'm pretty sure that isnt the problem. I will buy a ph meter tomm, if it is low, what can I do to raise it?

it looks like it needs watering to me but if you said the soil is moist im stumped...maybe search for root deficiencys...the way the plant is drooping and the leaf fringes standing up like that looks like its thirsty...try foliar feeding with some superthrive and water...not much about an 1/8th tsp per gallon....

Tested the ph and that is fine, so I added a lil water, hopefully that will do it, thanks guys!