Otherwise healthy leaves turning downwards?

Baby Girl is now 13 days old and she has been growing quite vigorously for the past 3-4 days. She is looking very healthy and the first set of fan leaves got a bit of heat stress I believe which caused the slight distortion. Since I have replaced bulbs and have been keeping an ambient temp. around 79-81 F. The newer set of leaves are growing very well, however, the tips are starting to turn downward. I have done some research and people say that it can be water related (over/underwatering) or a nitrogen overdose. I planted her as a germinated seed directly into a soil mix of 85% Fox Farms Ocean Forest and 15% Course Perlite. I laid a layer of perlite across the bottom for drainage as well as mixed in the soil and usually water her every 3-4 days. Usually the top 2 inches of the soil is completely dry before I water although I can get down to lower soil that is moist. I currently have 2-26w daylight-blue(6500K) cfls and 2-23w daylight(5000K) cfls on Y-connectors approximately 2-3 inches away from the canopy and run a 20/4 light cycle (Easy Rider Autoflower, ak-47 x low rider#2). Any ideas? Could even be lowish humidity levels..

I wouldnt be too concerned they look healthy. Maybe try to put a humidifier in there if you can, i know when they are young they tend to like the air more moist, i keep mine around 45-55%