Hey,
I had a look at the last photos.
You said you are 4 weeks into flowering.
I think you have a potassium deficiency. I might be wrong, maybe its a nutrient burn or light/heat burn.
You should check out this site and look at your leaves discolouration.

Plant abuse chart

If you are only 4 weeks in it may get a lot worse.
Would be worth checking out.

Your buds are looking good though. But you have to keep an eye on those leaves. Your plant might be telling you something.
The buds will thank you for it

Just my opinion.

take care