need help!!!

[TheChosenOne]

5th day of 12/12
i just put in a 400 watt mh light like a couple days ago and the second day i left the light on my plant just started having burns on the top of the plant. my plant is like 15" under the light and i have another plant under the same light like 10" under the light and it doesnt affect this plant
3rd pic shows both of the plants the one on the left looks a little droopy to thats the one with the burns
while the one on the right doesnt have any problems
maybe the pot is affecting something on the left plant cause i see roots comming out the bottom

 

[HippyInEngland]

Thats heat stress, are they the same strain seeds?

Have you got a fan blowing in your grow room?

What temperature is your grow room?

Time to re pot your burnt plant, the plant is obviously rootbound.

 

[TheChosenOne]

no there different strains i think
its bagseed i got from different baggies
yeah my fan is blowing 24/7
temp idk yet havent bought the temp reader thingy
is the root affecting why my plant on the left is looking a lil droopy?