Nutes or Heat??

Hi everyone I'm new 2 this growing stuff and just had a question...
I have 5 plants under 5 -43 watt cfl's I water every 2-3 days and givin' nutes every 2 weeks since birth its been about 5 weeks I also started the flowering stage 2 days ago.. and i have noticed dis-coloration and was wondering if you can help? It's just burnt looking.. Is It some kind of deficency???
I thought it was from the light being too close b/c it was mostly the top leaves and stuff...

so i tied a couple down and notice the smaller leaves on the bottom are starting to look burnt.. The only thing i can think of is that i dont have a fan moving the air around, MAYBE its too humid???

i can't see much of anything from those pics. soil folks usually feed once a week. what ppm are you feeding at what ph? airflow is really important. w/o it you could easily get rust.

From the pics they look like U overwatered them