Nug of the Year: 2016 - Member of the Month: Sept 2015, Nov 2016 - Nug of the Month: Oct 2016 - Plant of the Month: May 2016 - Photo of the Month: Nov 2020
when you make a post look at the bottom left corner. Where it says 'my photos'. You can post photos here that way. I looked at your gallery.
In your case it does look like heat stress to me. Is this plant in a hotspot, maybe closest to the light?
I peeked at your gallery too (Thanks Weas!).
You're leaves are just screamin that they're too hot.
Leaf margins (the saw teeth) curling up slightly are your fist sign. As this worsens, the entire sides of the leaf curl up and you hit "leaf taco" mode where the leaves resemble taco shells.
You're deep into a taco dinner.
While my plants start showing leaf margin issues around 100f, not all strains are the same. If I hit 105f, I'd be in taco mode myself.
Get your temps down. More fans. Less light. AC. Whatever it takes. Heat spikes can end your grow in a very quick way.