Looking at that left-hand pic a light leak would be a possible culprit, sure. It's easy to check; wait until dark, turn off all the lights in the room that your grow area is located- it should be PITCH black, don't stub yer toe- , go around looking for light escaping, add weatherstripping or duct tape if needed.
Heat stress could also cause those single-bladed leaves though so if you have that under control, and find no light leaks, just chalk it up to experience and be happy you got your temps down. For what those plants have been thoguh, it looks like they pulled through well. Nice work.