My first grow

Potassium deficiency. You are running way too much nitrogen in flowering as well. Shiney dark green is toxicity. Which nitrogen can hinder bud development in flowering when too much. Flowering NPK ratio is 1-2-3

I don't see any mold. It does look like those area's are a little more brown then the rest. This could be a nutrient imbalance or even just amber tricome's. They can pre-maturely go amber from abrasion. Happy Growing

Lots of options, I would wait for a boxing day sale before purchasing prob higher discounts then affiliated discounts. Or email them for a special deal from them because you missed Cyber Monday. You might also be able to get deep discounts from offering to buy lights at a cheaper rate in exchange for diaries on this platform. You just need to initiate the contact and go from there. Good Luck!