Add MH light and leaves fold??

[NewbieG]

So I've had this one plant for almost two weeks sitting by the window, its very small, has one set of leaves, then goes up a few inches and has another set of leaves of what looks like would form into the well known marijuana leaf pattern, but my question is that I just got a 400 watt MH set up, and I made the grow room, and put the plant in. To my surprise over a 7 hour period the top weed looking leaf folded up as if they were ungrowing?? the only problem I can think of with the grow room is that its too hot (possibly over 90 degrees, but can't tell) Any help on whats going on?

 

[50bud]

Back that light off, its like throwing it in to a fire its not use to that much light exposure.

 

[Growdude]

Yea back that light off, sounds like heat stress.

 

[shuggy4105]

how far do you have your light from the tops of the plants, and what way are the leaves "folding"?
you can`t have "too much" light.