Nitrogen Question; Soil

Ok heres my issue. First thank you to all that respond with MOST reliable info. I have an orange kush plant that I started from seed. I started it outside in the sunlight and it was there for about one week. As soon as I could, I transplanted it and moved it into a grow box that has a 100watt MH. Its been maybe 4 weeks(give or take) and the plant seems too small and the first set of leaves have gone yellow.Its almost 6 inches. The second set are kind of curled and seem dry with light brown spots. There are only 4 sets and the newest 2 are looking okay. I thought maybe the problem was heat stress because my box was reaching 100+ degrees. Now i have it at a constant 80-85 degrees. Now, when I transplanted this one I put it in Miracle Grow 21-12-7 about 2-3 weeks ago. Does this need nitrogen? I have Blood Meal that is 12%. The bag calls for 1 tblsp per 1sq ft area every "2 months" but is that enough?? Im soon switching to bubbleponics so I dont want to buy a tester. If pictures would help please let me know.

pics would def help
the first round leaves often die
the 100+ heat definatly stunted ur plants growth, as i suspect the transplant shock of moving it did aswell, sounds as if it could be burn aswell, becuase ive heard MG is bad for fully grown plants, letalone seedlings who barely need ANY nutes
that NPK has plenty of nitrogen in it aswell
hope i answered everything , anything elsE?

I know it had bad heat stress but it should have bounced back. How long until it should need nutes tho?