am i being paranoid?

Hey hows it going? So i woke up this morning and my plant has one leaf that is curling up around just 1 edge. Not sure if im being paranoid or not im hoping its just natural and not a problem. Lowest i can keep the temp is 80 until i can get a small ac unit. I watered it last night and didnt water it for about a day cause the soil was moist. Im using a 600w mh light thats 18" away from the plant. Btw should i start giving it nutes once a week now? I hope these nutes i have are ok and not to strong/weak.

It's fine. No need to change anything or try and fix it. Sometimes you get a retarded leaf.

When does it get down to 80? What light schedule are they on?

It looksike heat stress but 80 is not to hot. Around 86-90 you will see some leaf roll. It not permanent. Get the temps down. What is your humidity? I like real low humidity. 30-40% range lights on.

Also get a silica product. It helps with heat.

And for the nutes. The one you have has a lot of p and k. It is for flower. You need something for veg.
It is all salt. Go to any store that has a garden section and get a balanced fert like 5-5-5 or 10-10-10. If it doesn't have even numbers get something close like 5-4-4 or something.

Ok cool ty. Ya its 80 at the loweat with lights on its gotten up to 90 or so. At night it drops down to around 65-70ish. Im not sure about humidity i cant afford a meter till next month.