Dark spots on leaves forming

Raising your light is always a smart move when something bad is happening. Slowing down photosynthesis slows down everything. Autos at 4 weeks of flowering are at peak flowering and starts to swell up: She is hungry mate. Looks like P and or Cal deficiencies from here. QB style Led board are notorious for pushing the nutrient needs higher, especially for P, Mag and Cal, where the light hit the plants. You need to increase feeding. Frying some sugar leaves or top fan leaves is bad but not a catastrophe. If your 2 lights are at full power in your 2.3'x2.3'x5.2, that is a lot of light. Raise your light again if you can.